Answer:
27m
Step-by-step explanation:
It's the Pythagorean Theorem.
20^2+18^2=c^2
400+324=c^2
724=c^2
take the square root of both sides
26.9m=c
to the nearest meter = 27
Does the following systems produce an infinite number of solutions 2y + x = 4 ; 2y = -x +4
Answer:
Yes.
Step-by-step explanation:
In the future, simply plug both equations into Desmos.
I NEED HELP PLEASE, THANKS! :)
A music concert is organized at a memorial auditorium. The first row of the auditorium has 16 seats, the second row has 24 seats, the third row has 32 seats, and so on, increasing by 8 seats each row for a total of 50 rows. Find the number of people that can be accommodated in the sixteenth row. (Show work)
Answer: 136
Step-by-step explanation:
An= A1+(n-1)d
A1=16, d=8, and n=16
A16= 16 +(16-1)(8)
A16= 16(15)(8)
A16= 16+120
A16=136
Hey there! :)
Answer:
f(16) = 136 seats.
Step-by-step explanation:
This situation can be expressed as an explicit function where 'n' is the row number.
The question also states that the number of seats increases by 8. Use this in the equation:
f(n) = 16 + 8(n-1)
Solve for the number of seats in the 16th row by plugging in 16 for n:
f(16) = 16 + 8(16-1)
f(16) = 16 + 8(15)
f(16) = 16 + 120
f(16) = 136 seats.
A simple random sample of 20 items resulted in a sample mean of 10. The population standard deviation is = 3. Round your answers to two decimal places.
a. What is the standard error of the mean, ?
b. At 95% confidence, what is the margin of error?
Answer:
a. 0.67
b. 1.31
Step-by-step explanation:
We have the following information n = 20, mean (m) = 10 and standard deviation (sd) = 3
a.
SE (m) = sd / n ^ (1/2)
replacing we have:
SE (m) = 3/20 ^ (1/2) = 0.67
Therefore the standard error of the mean is 0.67
b.
the critical value is obtained as shown below:
the level of sifnificance is alfa = 1 - 0.95 = 0.05
the critical value with level of significance alfa / 2 = 0.05 / 2 = 0.025
and to this value corresponds z = 1.96 (z table)
The margin of error with 95 confidence is calculated as follows:
E = z * SE
E = 1.96 * 0.67
E = 1.31
Therefore the margin of error is 1.31
(a) The standard error will be "0.67".
(b) The margin of error will be "1.31".
According to the question,
Standard deviation,
sd = 3Sample size,
n = 20(a)
As we know,
→ The Standard error,
= [tex]\frac{sd}{\sqrt{n} }[/tex]
= [tex]\frac{3}{\sqrt{20} }[/tex]
= [tex]0.67[/tex]
(b)
As we know,
→ The margin of error,
= [tex]Z_{a/2}\times \frac{sd}{\sqrt{n} }[/tex]
By substituting the values, we get
= [tex]Z_{a/2}\times \frac{3}{\sqrt{20} }[/tex]
= [tex]1.96\times 0.67[/tex]
= [tex]1.31[/tex]
Thus the above response is right.
Learn more:
https://brainly.com/question/10501147
Simplify: |4-5| / 9 × 3³ - 2/5 a.61/10 b.13/5 c.11/10 d.-2/15
━━━━━━━☆☆━━━━━━━
▹ Answer
Answer = b. 13/5
▹ Step-by-Step Explanation
|4 - 5| ÷ 9 × 3³ - 2/5
|-1| ÷ 9 × 3³ - 2/5
1 ÷ 9 × 3³ - 2/5
1/9 × 3³ - 2/5
1/3² × 3³ - 2/5
3 - 2/5
Answer = 13/5
Hope this helps!
- CloutAnswers ❁
Brainliest is greatly appreciated!
━━━━━━━☆☆━━━━━━━
Answer:
[tex] \boxed{\sf b. \ \frac{13}{5}} [/tex]
Step-by-step explanation:
[tex] \sf Simplify \: the \: following: \\ \sf \implies \frac{ |4 - 5| }{9} \times {3}^{3} - \frac{2}{5} \\ \\ \sf 4 - 5 = - 1 : \\ \sf \implies \frac{ | - 1| }{9} \times {3}^{3} - \frac{2}{5} \\ \\ \sf Since \: - 1 \: is \: a \: negative \: constant, \: |-1| = 1: \\ \sf \implies \frac{1}{9} \times {3}^{3} - \frac{2}{5} \\ \\ \sf {3}^{3} = 3 \times {3}^{2} : \\ \sf \implies \frac{ \boxed{ \sf 3 \times {3}^{2}} }{9} - \frac{2}{5} \\ \\ \sf {3}^{2} = 9 : \\ \sf \implies \frac{3 \times 9}{9} - \frac{2}{5} \\ \\ \sf \frac{9}{9} = 1 : \\ \sf \implies 3 - \frac{2}{5} [/tex]
[tex] \sf Put \: 3 - \frac{2}{5} \: over \: the \: common \: denominator \: 5 : \\ \sf \implies 3 \times \frac{5}{5} - \frac{2}{5} \\ \\ \sf \implies \frac{3 \times 5}{5} - \frac{2}{5} \\ \\ \sf 3 \times 5 = 15 : \\ \sf \implies \frac{ \boxed{ \sf 15}}{5} - \frac{2}{5} \\ \\ \sf \implies \frac{15 - 2}{5} \\ \\ \sf 15 - 2 = 13 : \\ \sf \implies \frac{13}{5} [/tex]
Find the vector x determined by the given coordinate vector [x]B and the given basis B.
B = {[1 -3 1], [-3 8 3],[8 -2 3]}, [x]_B = [-3 -2 3]
a. [9 -13 0]
b. [0 -6 21]
c. [13 -24 -2]
d. [3 -13 16]
According to a recent study, some experts believe that 15% of all freshwater fish in a particular country have such high levels of mercury that they are dangerous to eat. Suppose a fish market has 150 fish we consider randomly sampled from the population of edible freshwater fish. Use the Central Limit Theorem (and the Empirical Rule) to find the approximate probability that the market will have a proportion of fish with dangerously high levels of mercury that is more than two standard errors above 0.15. You can use the Central Limit Theorem because the fish were randomly sampled; the population is more than 10 times 150; and n times p is 22.5, and n times (1 minus p) is 127.5, and both are more than 10.
Answer:
The approximate probability that the market will have a proportion of fish with dangerously high levels of mercury that is more than two standard errors above 0.15 is 0.95.
Step-by-step explanation:
According to the Central limit theorem, if from an unknown population large samples of sizes n > 30, are selected and the sample proportion for each sample is computed then the sampling distribution of sample proportion follows a Normal distribution.
The mean of this sampling distribution of sample proportion is:
[tex]\mu_{\hat p}=0.15[/tex]
The standard deviation of this sampling distribution of sample proportion is:
[tex]\sigma_{\hat p}=\sqrt{\frac{p(1-p)}{n}}[/tex]
As the sample size is large, i.e. n = 150 > 30, the central limit theorem can be used to approximate the sampling distribution of sample proportion by the normal distribution.
Compute the mean and standard deviation as follows:
[tex]\mu_{\hat p}=0.15\\\\\sigma_{\hat p}=\sqrt{\frac{p(1-p)}{n}}=\sqrt{\frac{0.15(1-0.15)}{150}}=0.0292[/tex]
So, [tex]\hat p\sim N(0.15, 0.0292^{2})[/tex]
In statistics, the 68–95–99.7 rule, also recognized as the empirical rule, is a shortcut used to recall that 68%, 95% and 99.7% of the Normal distribution lie within one, two and three standard deviations of the mean, respectively.
Then,
P (µ-σ < X < µ+σ) ≈ 0.68
P (µ-2σ <X < µ+2σ) ≈ 0.95
P (µ-3σ <X < µ+3σ) ≈ 0.997
Then the approximate probability that the market will have a proportion of fish with dangerously high levels of mercury that is more than two standard errors above 0.15 is 0.95.
That is:
[tex]P(\mu_{\hat p}-2\sigma_{\hat p}<\hat p<\mu_{\hat p}+2\sigma_{\hat p})=0.95\\\\P(0.15-2\cdot0.0292<\hat p<0.15+2\cdot0.0292)=0.95\\\\P(0.092<\hat p<0.208)=0.95[/tex]
Brainliest to whoever gets this correct This word problem has too much information. Which fact is not needed to solve the problem? Tanisha tried to sell all her old CDs at a garage sale. She priced them at $2 each. She put 80 CDs in the garage sale, but she sold only 35 of them. How many did she have left? A. All of the information is needed. B. Tanisha sold the CDs for $2 each. C. Tanisha put 80 CDs in the sale. D. Tanisha sold 35 of the CDs.
Answer:
B. Tanisha sold the CDs for $2 each.
Step-by-step explanation:
Which sentence in this excerpt from Common Sense by Thomas Paine supports the claim that the American colonies could thrive independently from Britain? I have heard it asserted by some, that as America hath flourished under her former connection with Great Britain that the same connection is necessary towards her future happiness, and will always have the same effect. Nothing can be more fallacious than this kind of argument. We may as well assert that because a child has thrived upon milk that it is never to have meat, or that the first twenty years of our lives is to become a precedent for the next twenty. But even this is admitting more than is true, for I answer roundly, that America would have flourished as much, and probably much more, had no European power had any thing to do with her. The commerce, by which she hath enriched herself, are the necessaries of life, and will always have a market while eating is the custom of Europe.
Answer:
A
Step-by-step explanation:
Answer:
"But even this is admitting more than is true, for I answer roundly, that America would have flourished as much, and probably much more, had no European power had any thing to do with her."
Step-by-step explanation:
Checked 2021
HELP PLEASE!!!! I NEED HELP ASAP Which statement best describes the expression 3 + y ÷ 2? The quotient of 2 and the sum of 3 and y The quotient of the sum of 3 and y, and 2 The sum of 3 and the quotient of 2 and y The sum of 3 and the quotient of y and 2
Answer:
I believe it is D
Answer:
The sum of 3 and the quotient of y and 2.
Step-by-step explanation:
The order of operations requires that you evaluate the expression ...
3 + y ÷ 2
by first performing the division, then the addition. So, the addition gives you the sum of 3 and a quotient, because the quotient must be evaluated first.
The quotient is of y and 2 (not 2 and y), because the wording "the quotient of a and b" is always interpreted to mean a÷b.
So, the expression can be described as ...
the sum of 3 and the quotient of y and 2.
pls pls help me help me help me
Answer:
2
Step-by-step explanation:
Answer:
I hope it will help you....
An adult has a total of about 22.5 square feet (ft2) of skin. Use the fact that 1 m is approximately equal to 3.281 feet to convert this measurement to square meters (m2). Round your answer to the nearest hundredth. Do not type the units in the space below.
Answer:
There are about 3.281 * 3.281 = 10.764 square feet in one square meter. Therefore, 22.5 square feet is 22.5 / 10.764 = 2.09 square meters.
Find the slope-intercept form of the line through (6, – 3) and perpendicular to the line y = 3x – 5.
Answer:
y=-1/3x-1
Step-by-step explanation:
We have the information y=3x-5, the lines are perpendicular, and the new line passes through (6,-3). The slopes of perpendicular lines are negative reciprocals so you need to find the negative reciprocal of 3, so flip it to 1/3 and multiply by -1, we get the slope of the new line as -1/3. So far we have the equation y=-1/3x+b. We are given a point on the line, (6,-3), so we can plug these into the equation as x and y to solve for the y-intercept, b. You set it up as -3=-1/3(6)+b. First you multiply to get -3=-2+b, then you add 2 to both sides to isolate the variable and you get b=-1. Then you can use b to complete your equation with y=-1/3x-1.
How do you write 0.0683 in scientific notation? ____× 10^____
Answer:
It's written as
[tex]6.83 \times {10}^{ - 2} [/tex]
Hope this helps you
Answer:
6.83 × 10 -2
hopefully this helped :3
3. A 12 % discount on a pair of washer and dryer that Gayle purchased, amounted to $156.00.
Calculate the net price.
Answer:
For this case we know that the price after the 12% of discount is 156 and we want to findd the net price so then we can use the following proportional rule:
[tex] \frac{x}{100} = \frac{156}{100-12}[/tex]
Where x represent the net price. And if we solve for the value of x we got:
[tex] x= 100 *\frac{156}{88}= 177.273[/tex]
So then the net price for this case would be $ 177.273
Step-by-step explanation:
For this case we know that the price after the 12% of discount is 156 and we want to findd the net price so then we can use the following proportional rule:
[tex] \frac{x}{100} = \frac{156}{100-12}[/tex]
Where x represent the net price. And if we solve for the value of x we got:
[tex] x= 100 *\frac{156}{88}= 177.273[/tex]
So then the net price for this case would be $ 177.273
Past studies have indicated that the percentage of smokers is estimated to be about 35%. Given the new smoking cessation programs that have been implemented, you now believe that the percentage of smokers has reduced. a) If you going to test this claim at the 0.05 significance level, what would be your null and alternative hypotheses
Answer:
H0: p = 3.5
H1: p < 3.5
Step-by-step explanation:
We are told that past studies have indicated that the percentage of smokers is estimated to be about 35%, but with the new smoking cessation programs that have been implemented, it is believed that the percentage of smokers has been reduced, we must propose our null and alternative hypotheses, which would be the following:
Null hypothesis: H0: p = 3.5
Alternative hypothesis: H1: p < 3.5
Find the percent of increase. Original Price: $200 Retail Price: $250
Answer:
The percent of increase is 25%
Step-by-step explanation:
Percentage increase = increase in price/original price × 100 = ($250 - $200)/$200 × 100 = $50/$200 × 100 = 25%
3
Select the correct answer.
What are the solutions to this equation?
16x² + 9 = 25
Answer:
Step-by-step explanation:
16x^2 + 9 = 25
16x^2 = 16
x^2 = 1
x = 1, -1
Denise is planning to put a deck in her back yard. The deck will be a 10-by-7-foot rectangle with a semicircle of diameter 4 feet, as shown below. Find the area of the deck (in square feet).(round your answer to two decimal places)
Answer:
[tex]approx. = 85.28 {ft}^{2} [/tex]
Step-by-step explanation:
You can think of this as adding the area of the rectangular portion of the deck (length x width) and the semicircular portion (πr^2)/2.
(l×w)+(πr^2)/2
(10×7)+((π2^2)/2
79+2π
[tex]approx. = 85.28 {ft}^{2} [/tex]
1. Which of these is a Pythagorean triple?
(a) (3, 4, 5)
(b) (5, 6, 7)
(c) (10, 11, 12)
(d) (15, 16, 17)
2. If y2 = 172 – 82. What is the value of y?
(a) 10
(b) 25
(c) 15
(d) 16
3. How many kilograms are there in 5 tonnes?
(a) 500 kg
(b) 50 000 kg
(c) 5, 000 kg
(d) 50 kg
4. If the probability that a girl win a race is 0.6. What is the probability that that the girl loses the race?
(a) 0.4
(b) 1
(c) 4
(d) 6
5. The distance from Lagos to Ibadan can be measured using which of the following units of measurement?
(a) centimeter
(b) Millimeter
(c) Kilograms
(d) Kilometer
6. The longest side of a right-angled triangle is called?
(a) right side
(b) Opposite
(c) Hypotenuse
(d) None of the above
7. The mass/weight of your pen can be measured using………
(a) Grams
(b) Kilometer
(c) Centimetre
(d) Tonne
8. There 5 blue balls, 8 red balls and 2 black balls in a basket. One ball is picked at random. Find the probability that the ball picked is red.
(a) 58
(b) 815
(c) 215
(d) 13
9. The mass of a lorry can be measured using which of the following?
(a) liter
(b) Kilometer
(c) Tonne
(d) Milligram
10. How many tonnes are there in 15 000 kg?
(a) 150 tonnes
(b) 15 tonnes
(c) 1500 tonnes
(d) 1.5 tonnes
11. What is 20% of #38 000?
(a) #7 600
(b) #3 800
(c) #2 800
(d) #760
12. Express 17:30 hours as a.m. or p.m. time.
(a) 7:30 pm
(b) 7:30 a.m.
(c) 5:30 p.m.
(d) 5:30 a.m.
13. Angle 900 is also called?
(a) left angle
(b) quarter angle
(c) right angle
(d) middle angle
14. “Kilo” is a Greek word from the word “khilioi” meaning what?
(a) Million
(b) Thousand
C) Billion
D) Hundred
15. Which is the most widely used system of measurement in the world?
(a) tape rule system
(b) counter system
(c) metric system
(d) none of the above
PART B
ANSWER ALL QUESTIONS
1. The largest unit of measurement for distance/length is kilometer. True or false …………………….
2. The probability that a student fails an examination is 0.2. What is the probability that the student passes the examination? .................
The members of a village cooperative agree to contribute time and money towards a one year village improvement programme (VIP). Below is the table of activities of the programme.
Activity
Time (hour)
Money(#)
Planting/ watering trees
300
20 000
Collecting/burning rubbish
200
0
Clearing storm ditches
80
5 000
Making speed bumps
20
5 000
3. How much is the total money pledged? …………..
4. Which activity takes more money? ………………..
5. Which activity cost no money? ……………………….
Answer
1. (a) (3,4,5)--3^2 +4^2=9+16=25=5^2
2. (b) 25--172-82=50/2=25
3. (c) 5,000 kg--1,000 kg in 1 tonne
4. (a) 0.4--1-0.6=0.4
5. (d) kilometer
6. (c) hypotenuse
7. (a) grams
8. i think it is (a) 58--5+8+2=15~~8/15 =0.53~closest answer is 58
9. (c) tonne
10. (b) 15 tonnes--1000 kg in 1 tonne
11. (a) #7,600--38000*20%, or 0.20, =7,600
12. (a) 7:30 pm
13. (c) right angle
(c) metric system
Part B
1. True
2. 0.8
3. 30,000 dollars--20,000 +0+5,000+5,000=30,000
4. Planting/watering trees--20 dollars
5. Collecting/burning rubbish--0 dollars
calculate find the area f a rectangle measuring 25 feet long by 8 feet wide
Answer: 200 ft²
Step-by-step explanation:
The area of a rectangle is length times width
So, simply do 25 * 8 = 200
Hey there! :)
Answer:
A = 200 ft².
Step-by-step explanation:
Use the formula A = l × w to determine the area of a rectangle:
A = 25 × 8
Multiply:
A = 200 ft².
The route used by a certain motorist in commuting to work contains two intersections with traffic signals. The probability that he must stop at the first signal is 0.36, the analogous probability for the second signal is 0.51, and the probability that he must stop at least one of the two signals is 0.67.What is theprobability that he must stop.
a) At both signals?
b) At the first signal but not at the second one?
c) At exactly on signal?
Answer:
a) P(X∩Y) = 0.2
b) [tex]P_1[/tex] = 0.16
c) P = 0.47
Step-by-step explanation:
Let's call X the event that the motorist must stop at the first signal and Y the event that the motorist must stop at the second signal.
So, P(X) = 0.36, P(Y) = 0.51 and P(X∪Y) = 0.67
Then, the probability P(X∩Y) that the motorist must stop at both signal can be calculated as:
P(X∩Y) = P(X) + P(Y) - P(X∪Y)
P(X∩Y) = 0.36 + 0.51 - 0.67
P(X∩Y) = 0.2
On the other hand, the probability [tex]P_1[/tex] that he must stop at the first signal but not at the second one can be calculated as:
[tex]P_1[/tex] = P(X) - P(X∩Y)
[tex]P_1[/tex] = 0.36 - 0.2 = 0.16
At the same way, the probability [tex]P_2[/tex] that he must stop at the second signal but not at the first one can be calculated as:
[tex]P_2[/tex] = P(Y) - P(X∩Y)
[tex]P_2[/tex] = 0.51 - 0.2 = 0.31
So, the probability that he must stop at exactly one signal is:
[tex]P = P_1+P_2\\P=0.16+0.31\\P=0.47[/tex]
I NEED HELP FAST, THANKS! :)
Answer:
33 units²
Step-by-step explanation:
A (graphing) calculator shows you that f(4) ≈ 8, and f(8) ≈ 8.5. The curve is almost a straight line between, so the area is approximately ...
A = (1/2)(8 + 8.5)(4) = 33
__
If you do the integration, it gets a bit messy.
[tex]\displaystyle\dfrac{5}{7}\int_4^8{x^{2/7}}\,dx+\dfrac{1}{2}\int_4^8{x^{4/9}}\,dx+\int_4^8{6}\,dx\\\\=\left.\left(\dfrac{5}{9}x^{9/7}+\dfrac{9}{26}x^{13/9}+6x\right)\right|_4^8\approx 33.16[/tex]
The appropriate answer choice is 33 square units.
Write a two column proof Given: AB || DC; BC || AE Prove: BC/EA = BD/EB
Answer:
Step-by-step explanation:
Given:
AB║DC and BC║AE
To prove:
[tex]\frac{\text{BC}}{\text{EA}}=\frac{\text{BD}}{\text{EB}}[/tex]
Statements Reasons
1). ∠ABE ≅ ∠CDB 1). Alternate interior angles
2). ∠AEB ≅ ∠CBD 2). Alternate interior angles
3). ΔCBD ~ ΔAEB 3). AA property of similarity
4). [tex]\frac{\text{BC}}{\text{EA}}=\frac{\text{BD}}{\text{EB}}[/tex] 4). Property of similarity [Corresponding sides of two similar triangles are proportional]
by how much is 25% of #25 greater than 15% of #15
Answer:
4
Step-by-step explanation:
25% of 25
0.25 × 25 = 6.25
15% of 15
0.15 × 15 = 2.25
Find the difference.
6.25 - 2.25
= 4
In triangle ABC, the right angle is at vertex C, a = 714 cm and the measure of angle A is 78° . To the nearest cm, what is the length of side c?
Answer:
c = 730cm
Step-by-step explanation:
The first thing we would do is to draw the diagram using th given information.
Find attached the diagram.
a = 714 cm
the measure of angle A = 78°
To determine c, we would apply sine rule. This is because we know the opposite and we are to determine the hypotenuse
sin78 = opposite/hypotenuse
sin 78 = 714/c
c = 714/sin 78 = 714/0.9781
c= 729.99
c≅ 730 cm ( nearest cm)
HELP ASAP! The number of entertainment websites in 1995 wass 54. By 2004 there were 793 entertainment website..
Approximately, what was the rate of change for the number of the websites for this time period??
=============================================================
How I got that answer:
We have gone from 54 websites to 793 websites. This is a change of 793-54 = 739 new websites. This is over a timespan of 2004-1995 = 9 years.
Since we have 739 new websites over the course of 9 years, this means the rate of change is 739/9 = 82.1111... where the '1's go on forever. Rounding to the nearest whole number gets us roughly 82 websites a year.
----------
You could use the slope formula to get the job done. This is because the slope represents the rise over run
slope = rise/run
The rise is how much the number of websites have gone up or down. The run is the amount of time that has passed by. So slope = rise/run = 739/9 = 82.111...
In a more written out way, the steps would be
slope = rise/run
slope = (y2-y1)/(x2-x1)
slope = (793 - 54)/(2004 - 1995)
slope = 739/9
slope = 82.111....
Christopher collected data from a random sample of 800 voters in his state asking whether or not they would vote to reelect the current governor. Based on the results, he reports that 54% of the voters in his city would vote to reelect the current governor. Why is this statistic misleading?
Answer:
The statistic is misleading because Christopher collects his sample from a population (voters in his state) and make inferences about another population (voters in his city).
Step-by-step explanation:
The statistic is misleading because Christopher collects his sample from a population (voters in his state) and make inferences about another population (voters in his city).
He should make inferences about the population that is well represented by his sample (voters in his state), or take a sample only from voters from his city to make inferences about them.
. The client was hoping for a likability score of at least 5.2. Use your sample mean and standard deviation identified in the answer to question 1 to complete the following table for the margins of error and confidence intervals at different confidence levels. Note: No further calculations are needed for the sample mean. (6 points: 2 points for each completed row) Confidence Level | Margin of error | Center interval | upper interval | Lower interval 68 95 99.7
Answer:
The 68% confidence interval is (6.3, 6.7).
The 95% confidence interval is (6.1, 6.9).
The 99.7% confidence interval is (5.9, 7.1).
Step-by-step explanation:
The Central Limit Theorem states that if we have a population with mean μ and standard deviation σ and take appropriately huge random-samples (n ≥ 30) from the population with replacement, then the distribution of the sample-means will be approximately normally distributed.
Then, the mean of the sample means is given by,
[tex]\mu_{\bar x}=\bar x[/tex]
And the standard deviation of the sample means (also known as the standard error)is given by,
[tex]\sigma_{\bar x}=\frac{\sigma}{\sqrt{n}} \ \text{or}\ \frac{s}{\sqrt{n}}[/tex]
The information provided is:
[tex]n=400\\\\\bar x=6.5\\\\s=4[/tex]
As n = 400 > 30, the sampling distribution of the sample-means will be approximately normally distributed.
(a)
Compute the 68% confidence interval for population mean as follows:
[tex]CI=\bar x\pm z_{\alpha/2}\cdot \frac{s}{\sqrt{n}}[/tex]
[tex]=6.5\pm 0.9945\cdot \frac{4}{\sqrt{400}}\\\\=6.5\pm 0.1989\\\\=(6.3011, 6.6989)\\\\\approx (6.3, 6.7)[/tex]
The 68% confidence interval is (6.3, 6.7).
The margin of error is:
[tex]MOE=\frac{UL-LL}{2}=\frac{6.7-6.3}{2}=0.20[/tex]
(b)
Compute the 95% confidence interval for population mean as follows:
[tex]CI=\bar x\pm z_{\alpha/2}\cdot \frac{s}{\sqrt{n}}[/tex]
[tex]=6.5\pm 1.96\cdot \frac{4}{\sqrt{400}}\\\\=6.5\pm 0.392\\\\=(6.108, 6.892)\\\\\approx (6.1, 6.9)[/tex]
The 95% confidence interval is (6.1, 6.9).
The margin of error is:
[tex]MOE=\frac{UL-LL}{2}=\frac{6.9-6.1}{2}=0.40[/tex]
(c)
Compute the 99.7% confidence interval for population mean as follows:
[tex]CI=\bar x\pm z_{\alpha/2}\cdot \frac{s}{\sqrt{n}}[/tex]
[tex]=6.5\pm 0.594\cdot \frac{4}{\sqrt{400}}\\\\=6.5\pm 0.392\\\\=(5.906, 7.094)\\\\\approx (5.9, 7.1)[/tex]
The 99.7% confidence interval is (5.9, 7.1).
The margin of error is:
[tex]MOE=\frac{UL-LL}{2}=\frac{7.1-5.9}{2}=0.55[/tex]
Show all work to solve 3x^2 – 5x – 2 = 0.
Answer:
Step-by-step explanation:
3x2−5x−2=0
For this equation: a=3, b=-5, c=-2
3x2+−5x+−2=0
Step 1: Use quadratic formula with a=3, b=-5, c=-2.
x= (−b±√b2−4ac )2a
x= (−(−5)±√(−5)2−4(3)(−2) )/2(3)
x= (5±√49 )/6
x=2 or x= −1 /3
Answer:
x=2 or x= −1/ 3
The solutions to the equation are x = -1/3 and x = 2.
Here are the steps on how to solve [tex]3x^{2}[/tex] – 5x – 2 = 0:
First, we need to factor the polynomial. The factors of 3 are 1, 3, and the factors of -2 are -1, 2. The coefficient on the x term is -5, so we need to find two numbers that add up to -5 and multiply to -2. The two numbers -1 and 2 satisfy both conditions, so the factored polynomial is (3x + 1)(x - 2).
Next, we set each factor equal to 0 and solve for x.
(3x + 1)(x - 2) = 0
3x + 1 = 0
3x = -1
x = -1/3
x - 2 = 0
x = 2
Therefore, the solutions to the equation [tex]3x^{2}[/tex] – 5x – 2 = 0 are x = -1/3 and x = 2.
Here is the explanation for each of the steps:
Step 1: In order to factor the polynomial, we need to find two numbers that add up to -5 and multiply to -2. The two numbers -1 and 2 satisfy both conditions, so the factored polynomial is (3x + 1)(x - 2).
Step 2: We set each factor equal to 0 and solve for x. When we set 3x + 1 equal to 0, we get x = -1/3. When we set x - 2 equal to 0, we get x = 2. Therefore, the solutions to the equation are x = -1/3 and x = 2.
Learn more about equation here: brainly.com/question/29657983
#SPJ2
Find the critical value z Subscript alpha divided by 2 that corresponds to the given confidence level. 80%
Answer:
[tex] Conf= 0.80[/tex]
With the confidence level we can find the significance level:
[tex]\alpha =1-0.8=0.2[/tex]
And the value for [tex]\alpha/2=0.1[/tex]. Then we can use the normal standard distribution and we can find a quantile who accumulates 0.1 of the area on each tail and we got:
[tex] z_{\alpha/2}= \pm 1.28[/tex]
Step-by-step explanation:
For this problem we have the confidence level given
[tex] Conf= 0.80[/tex]
With the confidence level we can find the significance level:
[tex]\alpha =1-0.8=0.2[/tex]
And the value for [tex]\alpha/2=0.1[/tex]. Then we can use the normal standard distribution and we can find a quantile who accumulates 0.1 of the area on each tail and we got:
[tex] z_{\alpha/2}= \pm 1.28[/tex]