Answer:
x = 10
Step-by-step explanation:
I made a right triangle with a leg of 6 (7-1), base of 7, and hypotenuse of 'x' and then used the pythagorean theorem:
6² + 8² = x²
100 = x²
x = √100
x = 10
Peter buried a treasure chest on a remote island and is.making a map so he can find it later. One of the key landmarks in the area is a small rectangle hut, 5m by 8m
In a study of academic procrastination, the authors of a paper reported that for a sample of 451 undergraduate students at a midsize public university preparing for a final exam in an introductory psychology course, the mean time spent studying for the exam was 7.74 hours and the standard deviation of study times was 3.10 hours. For purposes of this exercise, assume that it is reasonable to regard this sample as representative of students taking introductory psychology at this university.
(a) Construct a 95% confidence interval to estimate μ, the mean time spent studying for the final exam for students taking introductory psychology at this university. (Round your answers to three decimal places.) TWO VALUES
(b) The paper also gave the following sample statistics for the percentage of study time that occurred in the 24 hours prior to the exam.
n = 451 x = 43.78 s = 21.96
Construct a 90% confidence interval for the mean percentage of study time that occurs in the 24 hours prior to the exam. (Round your answers to three decimal places.)
Answer:
a) The 95% confidence interval to estimate μ is (7.435, 8.045) hours.
b) The 90% confidence interval for the mean percentage of study time that occurs in the 24 hours prior to the exam is (41.079%, 45.481%).
Step-by-step explanation:
Question a:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
[tex]M = 1.96\frac{3.3}{\sqrt{451}} = 0.305[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 7.74 - 0.305 = 7.435 hours
The upper end of the interval is the sample mean added to M. So it is 7.74 + 0.305 = 8.045 hours.
The 95% confidence interval to estimate μ is (7.435, 8.045) hours.
Question b:
90% confidence interval means that [tex]Z = 1.645[/tex]
The margin of error is:
[tex]M = 1.645\frac{21.96}{\sqrt{451}} = 1.701[/tex]
43.78 - 1.701 = 41.079%
43.78 + 1.701 = 45.481%
The 90% confidence interval for the mean percentage of study time that occurs in the 24 hours prior to the exam is (41.079%, 45.481%).
help pls pls pls シ
And thanks!
Answer:
the answer the 10.25 u move both decimals over and move it up to the top and divide like normal
Evaluate the indicated limit algebraically. Change the form of the function where necessary. Please write clearly with description of each step, thank you very much.
3x^2+4.5
________
x^2-1.5
lim
x → ∞
Answer:
[tex]\displaystyle \lim_{x\to \infty}\frac{3x^2+4.5}{x^2-1.5}=3[/tex]
Step-by-step explanation:
We want to evaluate the limit:
[tex]\displaystyle \lim_{x\to \infty}\frac{3x^2+4.5}{x^2-1.5}[/tex]
To do so, we can divide everything by x². So:
[tex]=\displaystyle \lim_{x\to \infty}\frac{3+4.5/x^2}{1-1.5/x^2}[/tex]
Now, we can apply direct substitution:
[tex]\Rightarrow \displaystyle \frac{3+4.5/(\infty)^2}{1-1.5/(\infty)^2}[/tex]
Any constant value over infinity tends towards 0. Therefore:
[tex]\displaystyle =\frac{3+0}{1+0}=\frac{3}{1}=3[/tex]
Hence:
[tex]\displaystyle \lim_{x\to \infty}\frac{3x^2+4.5}{x^2-1.5}=3[/tex]
Alternatively, we can simply consider the biggest term of the numerator and the denominator. The term with the strongest influence in the numerator is 3x², and in the denominator it is x². So:
[tex]\displaystyle \Rightarrow \lim_{x\to\infty}\frac{3x^2}{x^2}[/tex]
Simplify:
[tex]\displaystyle =\lim_{x\to\infty}3=3[/tex]
The limit of a constant is simply the constant.
We acquire the same answer.
simplify 8x+7-x-4
help meeeeee!!!
Answer:
7x + 3
Step-by-step explanation:
Let's simplify step-by-step.
8x + 7 − x − 4
= 8x + 7 + −x + −4
Combine Like Terms:
= 8x + 7 + −x + −4
= (8x + −x) + (7 + −4)
= 7x + 3
Answer:
= 7x + 3
hope this helps and is right. p.s i really need brainliest :)
if my answer is wrong then I am incredibly sorry!
5m²+15m=0
t²-5t+6=0
5p²+12p+4=0
2a²+10a-48=0
x(2x+5)=0
Answer:
m=1, m= -3
t=3, t=2
p= -0.4, p= -2
a= 3, a= -8
x=0, x= -2.5
Answer:
I hope this helps a little bit.
It Is Not Fake
It Got Answers Promise
count the numbers of triangles in the figures
Answer:
A
Step-by-step explanation:
look it carefully.
What is the approximate value of 12−−√ ?
3.5
2
6
4.5
If f(x)= x squared and g(x)=2x^3- x squared, find f(x)-g(x).
Answer:
[tex]f(x)-g(x)=2x^2(1-x)[/tex]
Step-by-step explanation:
Given that,
[tex]f(x)=x^2\\\\g(x)=2x^3-x^2[/tex]
We need to find the value of f(x)-g(x).
Put the values of f(x) and g(x). So,
[tex]f(x)-g(x)=x^2-(2x^3-x^2)\\\\=x^2-2x^3+x^2\\\\=2x^2-2x^3\\\\=2x^2(1-x)[/tex]
So, the value of f(x)-g(x) is equal to [tex]2x^2(1-x)[/tex].
Find the value of f(4) for the function
Answer:
f(4) = 7
Step-by-step explanation:
The notation for these type of problems is very confusing. Just remember that f(x) is the same thing as y (or some variable). Even if there is a number or something on the inside of the parentheses, it's still just a variable.
In our case
f(a) = 2(a + 4) -9
could be rewritten as
y = 2(a + 4) - 9
the thing on the inside of the parentheses signifies what the equation is dependent on.
so when is says f(4), it just want's you to trade out a for a 4, but the equation is still the same.
f(4) = 2((4) + 4) - 9
Now, just follow the order of operations
f(4) = 2(8) - 9
f(4) = 16 - 9
f(4) = 7
Help me please, I don’t understand this at all
Answer: d
Step-by-step explanation:
aint no 90 cuz
Answer:
Not a right triangle
Step-by-step explanation:
root 4^2 + 6^2 is not equal to 7.5
Please only answer if you're 100% sure it's correct. Thank you. (It's pretty easy.)
The volume of a fish tank is 70 cubic feet. If the density is 0.4 fish over feet cubed, how many fish are in the tank?
175
88
28
14
Answer:
28 fish is the correct answer
Step-by-step explanation:.
The number of fish in the fish tank will be 28.
What is a volume?Volume is defined as the space occupied by any object in the three-Dimensions. All three parameters are required for the volume like length, width, and height of the Cuboid.
The density of the fish is defined as the number of fish per unit volume of the tank.
Given that volume of a fish tank is 70 cubic feet and the density is 0.4 fish over feet cubed.
The number of fish is calculated as below:-
Number = Volume of tank x Density of fish
Number = 70 x 0.4
Number = 28 fish
Therefore, the number of fish in the fish tank will be 28.
To know more about volume follow
https://brainly.com/question/1972490
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Which statement can be used to find X
Answer:
it's letter D. cos 16⁰=²¹--x
Which of the following is false about the figure?
a. m CUD = m VUM
b. M AUV + m DUA = 180
c. m MUC - m MUD = mzCUD
d. m PUD + m VUP = m PUM + m_CUA
Answer:
d.
Step-by-step explanation:
Let's examine each statement:
Option A: m<CUD = m<VUM (CORRECT)
Rationale: vertical angles are congruent to each other.
Option B: m<AUV + m<DUA = 180 (CORRECT)
Rationale: angles on a straight line
Option C: m<MUC - m<MUD = m<CUD (CORRECT)
Rationale:
m<MUC = m<MUD + m<CUD
Subtract m<MUD from each side
m<MUC - m<MUD = m<CUD
Option D is FALSE
Rationale:
m<PUD + m <VUP = 180° (angles on a straight line)
m<PUM + m<CUA ≠ 180°
Therefore,
m<PUD + m<VUP = m<PUM + m<CUA IS FALSE.
What single percentage change is equivalent to a 11% decrease followed by a 13% decrease?
Answer:
77.43% decrease
Step-by-step explanation:
A decrease of 11% = (100 - 11)% = 89% = [tex]\frac{89}{100}[/tex] = 0.89
A decrease of 13% = (100 - 13)% = 87% = [tex]\frac{87}{100}[/tex] = 0.87
A 11% decrease followed by a 13% decrease has an overall change of
0.89 × 0.87 = 0.7743 × 100% = 77.43%
Pay the bill using the fewest possible bills/coins
Answers:
Open the pdf below and youll find what you need. also do the largest bills you can.
someone please help me answer this!!
Answer:
c = 8.4m is the answer.
Step-by-step explanation:
a = 6m
b = 6m
c = ?
According to the Pythagorean theorem,
a² + b² = c²
6² + 6² = c²
36 + 36 = c²
c² = 72
c = 8.4m
∴ The mouse runs 8.4 m from the opposite corners of the room.
Answer:
8.5 m
Step-by-step explanation:
If you draw the segment from one corner to the opposite corner, you'll have the hypotenuse of a triangle with two legs of 6 m. We can find the length of the hypotenuse using the Pythagorean Theorem.
a^2 + b^2 = c^2
6^2 + 6^2 = c^2
36 + 36 = c^2
c^2 = 72
c = sqrt(72)
c = 6sqrt(2) = 8.5
Answer: 8.5 m
Classify the angle pair using all names that apply
Answer:
Vertical and supplementary
Step-by-step explanation:
Angles 1 and 2 are Vertically opposite angles and therefore they are equal to each other.
Amy and Sara's ages are consecutive even integers. The product of their ages is 528. If Sara is
younger, how old is Amy?
Write an equation that can be used to find their ages.
Answer:
24
Step-by-step explanation:
Sara = x age
Amy = x+2 when Sara x = 22 Amy is x + 2 = 24
Product of ages = 528 so............
x(x+2) = 528
x² + 2x - 528 = 0 solve for x I did it graphically first to get x = -24, 22
(x+24) (x-22) = 0
(x+24) = 0 (x-22) = 0
x = -24 x = 22 since you really can't have a negative age
I need help with a Delta math Assignment
Gabriella made 5% of her free throws over the season. If she shot 180 free throws, how many did she make?
Answer:
9
Step-by-step explanation:
Rewrite as an exponential equation.
In7 = y
what is the value of 4/15÷2/3
Answer:
2 /5
Step-by-step explanation:
Sin 17° cos 13° + cos 17° sin 13°
Answer:
.5
Step-by-step explanation:
Sin(x)cos(y) + cos(x)sin(y) = sin(x+y)
sin(17+13) = 1/2
what is 5 cm in mm. i need a simple answer. NO LINKS
50 millimeters
keystrokes
the price per gallon of gas with a $7 car wash is $3.19 and the price without the car wash is $3.39. When is it worth it to buy the car wash? When is it worth it if the car wash costs $2?
Answer:
The price per gallon of gas with a $7 car wash is $3.19
Then if you purchase x gallons of gas and also pay for the car wash, the total cost is:
C(x) = $7 + $3.19*x
In the case that you do not pay for the car wash, the cost per gallon is $3.39
Then the cost for x gallons of gas in this case is:
K(x) = $3.39*x
When is it worth it to buy the car wash?
We need to sett the equations:
C(x) = K(x)
This means that you pay exactly the same in both cases, but in one ( C(x)) you get the car wash and in the other not.
Then we need to solve:
$7 + $3.19*x = $3.39*x
$7 = ($3.39 - $3.19)*x = $0.20*x
$7/$0.20 = x = 35
Then for 35 gallons, is worth to buy the car wash.
In the case where the car wash costs $2, then the equation C(x) becomes:
C(x) = $2 + $3.19*x
Then if we solve the same equation:
C(x) =K(x)
$2 + $3.19*x = $3.39*x
$2 = ($3.39 - $3.19)*x
$2 = $0.20*x
$2/$0.20 = x
10 = x
Then for 10 galons is whort buy the car wash.
Question 17
17. Find the scale factor that was used in the dilation shown.
Answer:
We are missing a picture, we can't see the dilation they are referring to. The photo is just showing the answer options, so without the dilation it can't be answered.
Step-by-step explanation:
help plz plz plz ill give brain
n a study to investigate whether vitamin C will prevent colds, 400 subjects are assigned at random to one of two groups. The experimental group takes a vitamin C tablet daily, while the control group takes a placebo. At the end of the experiment, the researchers calculate the difference between the percentage of subjects in the two groups who were free of colds. This difference is statistically significant (P=0.03) in favor of the vitamin C group.
Answer:
Step-by-step explanation:
The aim of this question is to see if we can infer and conclude that vitamin C has a good impact in preventing colds based on the evidence provided.
Null hypothesis: Vitamin C has no effect on preventing colds.
Alternative hypothesis: Vitamin C has a strong effect on preventing colds.
Assuming, significance level = 0.05
Since the p-value for the difference is 0.03 which is less than 0.05.
Hence, the null hypothesis is rejected (which is there is no effect of vitamin C).
As a result, it can be concluded that Vitamin C has a major impact on the prevention of colds.
what is the answer to this?
Answer:
i can only say that you should use this forumla, the sins law
sin(a)/A = sin(b)/B = sin(c)/C
Step-by-step explanation: