Answer:
2x - 3 = 7
Step-by-step explanation:
Equation:
2x - 3 = 7
-------------------------
Solution:
Add 3 to both sides
2x = 10
Divide bothsides by 2
x = 5
-------------------------------
Proof
2x - 3 = 7
plug in x = 5
2(5) - 3 = 7
10 - 3 = 7
7 = 7
What conditions in the nucleus are likely to result in an atom that is unstable?
A. When the attraction of the electrostatic force is greater than the
repulsion of the strong force
B. When the repulsion of the electrostatic force is greater than the
attraction of the strong force
C. When the attraction of the electrostatic force is greater than the
attraction of the strong force
D. When the repulsion of the electrostatic force is weaker than the
repulsion of the strong force
Answer: D. When the attraction of the strong force is weaker than the repulsion of the electrostatic force
Step-by-step explanation: An atom is stable if the forces among the particles that makeup the nucleus are balanced. An atom is unstable (radioactive) if these forces are unbalanced; if the nucleus has an excess of internal energy. Instability of an atom's nucleus may result from an excess of either neutrons or protons.
Which subtraction sentence shows the difference
Answer:
A
Step-by-step explanation:
because box is filled with four out of six and the second is filled with three out of six. So, you subtract the second one from the first one. I HOPE IT HELPS
Find the length of chord AB. Assume the graph is scaled by ones. Give exact and
approximate answers. Round to the nearest hundredth.
O sqrt(34); 5.83 units
O sqrt(24): 4.90 units
O sqrt(26): 5.10 units
O sqrt(10): 3.16 units
Answer: Choice C
exact length = sqrt(26) units
approximate length = 5.10 units
=======================================================
Work Shown:
We can use the distance formula.
A = (x1,y1) = (2,2)
B = (x2,y2) = (1,-3)
[tex]d = \sqrt{(x_1 - x_2)^2 + (y_1 - y_2)^2}\\\\d = \sqrt{(2-1)^2 + (2-(-3))^2}\\\\d = \sqrt{(2-1)^2 + (2+3)^2}\\\\d = \sqrt{(1)^2 + (5)^2}\\\\d = \sqrt{1 + 25}\\\\d = \sqrt{26}\\\\d \approx 5.0990195\\\\d \approx 5.10\\\\[/tex]
The distance from A to B is exactly sqrt(26) units which approximates to 5.10 units. This distance represents the length of chord AB.
A market researcher would like to know how much time the average college student spends watching sports. Suppose he does a preliminary study based upon a sample of 25 college students. The mean amount of time spent watching sports, by those in the sample, is 90 minutes per day with a standard deviation of 15 minutes per day.
(a) Which of the following numbers gives the value of the point estimate?
a. 15.
b. 25.
c. 90.
d. 0.
e. 95.
(b) Using the information given above, calculate the margin of error (in minutes) of the point estimate. Assume we would like to estimate the population mean with 95% confidence.
(c) Suppose that the researcher is not content with the current margin of error. He would like the margin of error of the point estimate to be no more than 4 minutes with 95% confidence. The researcher is unwilling to trust that the sample standard deviation from his previous study accurately estimates the true population standard deviation. He does, however, know that college students tend to watch sports between 0 and 120 minutes per day. What is the minimum sample size needed to obtain this amount of precision?
Answer:
a) c. 90.
b) The margin of error of the point estimate is of 6.19 minutes.
c) The minimum sample size needed to obtain this amount of precision is 289.
Step-by-step explanation:
(a) Which of the following numbers gives the value of the point estimate?
The value of the point estimate is the sample mean, of 90 minutes. So the answer is given by option c.
(b) Using the information given above, calculate the margin of error (in minutes) of the point estimate. Assume we would like to estimate the population mean with 95% confidence.
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 25 - 1 = 24
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 24 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 2.0639.
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}}[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
Here, we have [tex]s = 15, n = 25[/tex]. So
[tex]M = T\frac{s}{\sqrt{n}}[/tex]
[tex]M = 2.0639\frac{15}{\sqrt{25}}[/tex]
[tex]M = 6.19[/tex]
The margin of error of the point estimate is of 6.19 minutes.
Question c:
College students tend to watch sports between 0 and 120 minutes per day, which means that the standard deviation for population can be estimated as the standard deviation of an uniform distribution with [tex]a = 0, b = 120[/tex]. This standard deviation is:
[tex]\sigma = \sqrt{\frac{(b-a)^2}{12}}[/tex]
Then
[tex]\sigma = \sqrt{\frac{(120-0)^2}{12}}[/tex]
[tex]\sigma = 34.64[/tex]
Minimum sample size:
Now, since we have an estimate for the standard deviation of the population, we use the z-distribution.
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.
The minimum sample size is n for which M = 4. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]4 = 1.96\frac{34.64}{\sqrt{n}}[/tex]
[tex]4\sqrt{n} = 1.96*34.64[/tex]
[tex]\sqrt{n} = \frac{1.96*34.64}{4}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*34.64}{4})^2[/tex]
[tex]n = 288.1[/tex]
Rounding up:
The minimum sample size needed to obtain this amount of precision is 289.
The radius of a cylinder is 5 cm and the height is 7 cm.
Find the volume of the cylinder.
O 17517
7011
12011
No answer text provided.
Answer:
V = πr²h
V = 3.14 (5cm)²(7 cm)
V = 3.14 (25cm²) ( 7 cm)
V = 3.14 (175 cm³)
V = 549.50 cm³
a $2500 bond earns 3% interest per year, compounded annually
a) write a function, V, that models the value of the bond t years after it is purchased.
b)find the value of the bond after each of the first five years
Answer:
Step-by-step explanation:
What is the area of a quadrilateral with vertices at (2,-4), (4,-4), (2,1), and (4, 1).
How many units squared?
An equation with real coefficients has (1-i), 3, and 4 among its roots. What is the lowest possible degree of the equation?
A: 3
B: 4
C: 5
D: 6
Answer:
D
Step-by-step explanation:
John's parents deposited $1000 into a savings account as a college fund when
he was born. How much will John have in this account after 18 years at a yearly
simple interest rate of 3.25%?
Answer: 15850
Step-by-step explanation:
if johns account has 10000 dollars then each year he'll be making at 3.25% interest that's a total of $325 each year therefore in 18 years he'll have made 325 X the 18 years which you turn hall to 5850 as interest but now the question is it asking how much will John have in his account after 18 years at the yearly simple interest of the 3.25 there for the total will be 15850 dollars
Can someone help me I am stuck on this question it would mean the world if u helped me! and TYSM! for the people who helped me have a wonder full day!
Answer:
1.25 gallons of orange juice needed
Step-by-step explanation:
2(3/4)=3/2 cups per 1 person
24 x 3/2=36 cups for everyone
36 cups=18 pints
18-8=10 pints of orange juice
10 pints = 1.25 gallon
Answer:
1.25 gallons of orange juice
Step-by-step explanation:
24x2=48
3/4x48=36
36 cups into pints is 18 pints
18-8=10
10 pints into gallons is 1.25 gallons
20 points and brainliest!
Best answers please
Answer:
x = 12
Step-by-step explanation:
= 6 * (1/6 x)
= (6) * (2)
x = 12
Hope this helps....
Have a good day ahead :)
Answer:
The awnser is D) X=12
Step-by-step explanation:
Its not A because 1/12 times 1/6 is 1/72 and that's not equal to the sum.Its not B because 1/3 times 1/6 is 1/18 and that's not equal to the sum.Its not C because 1/6 times 3 is 1/2 and thats not equal to the sum.So, It has to be D. TO show my work, 12 times 1/6 is 2/1 and that is 2. It is equal to the sum.Sorry if its blurry:<
Which plot has an outlier?
Answer:
girls
Step-by-step explanation:
an outlier is a number that is greater than the others.
boys doesnt have and outlier because the highest number has other numbers near it, while girls doesn't.
If 10x =5 what is x
X=1/2
X=log10 5
X=5/log10 10
X=in 5
Please help I really need help. I am super confused and would really appreciate it
Answer:
[tex] a^{5} [/tex]
Step-by-step explanation:
Given the mathematical expression;
a⁸/a³
To rewrite the expression in the form [tex] a^{m} [/tex]
We would have to apply the law of indices.
[tex] Law \; of \; division = \frac {a^{x}}{a^{y}} = a^{x - y} [/tex]
[tex] Law \; of \; division = \frac {a^{8}}{a^{3}} = a^{8 - 3} [/tex]
[tex] a^{m} = a^{8 - 3} = a^{5} [/tex]
an official playing field (including end zone) for the indoor football league has a length 39 yd longer than its width. the perimeter of the rectangular field is 162 yd. find the length
Answer:
42
Step-by-step explanation:
39+39 = 78
162 - 78 = 2 lengths =84
84/2 = 42
WHAT IS 5 TIMES 2 I NEED HELP ASAP BECAUSE I CANT KEEP UP UGHHHH
Answer:
2X2
Step-by-step explanation:
Answer: 10
Step-by-step explanation: 5 x 2 = 10
5 + 5 = 10
What is the range of function g
Answer:
C. (-∞, 1)
Step-by-step explanation:
The function is translated by shifting one up and reflecting over the x-axis, so its maximum value will be approaching 1 and its minimum value will be approaching infinity.
find the common difference of the arithmetic sequence 3, -2, -7
Answer:
-5
Step-by-step explanation:
To find the common difference, take the second term and subtract the first term
-2 - 3 = -5
Check with the third term and the second term
-7 - (-2) = -7 +2 = -5
The common difference is -5
3) b) Solve for x using the quadratic formula.
2x2 + x-1=0
Answer: x = -3
Step-by-step explanation:
2 x 2 + x - 1 = 0
4 + x - 1 = 0
3 + x = 0
x = -3
Answer:
X=-3
Step-by-step explanation:
See steps below:)
Classify the following triangle. Check all that apply.
A
I A. Equilateral
B. Right
C. Acute
I D. Isosceles
O E Obtuse
O F. Scalene
Answer:
A and C
Step-by-step explanation:
The triangle given has three equal sides and three equal angles.
Since the sum of a triangle = 180°, therefore, each angle equals 60°
Thus, we can conclude that the triangle is an acute triangle because an acute triangle has all three sides measuring less than 90°. This implies that all it's angles are acute angles.
Also, since all its sides are equal and the same as well as it's three angles, based on this, we can equally say the triangle is an equilateral triangle.
The triangle can be referred to as an acute triangle and also as an equilateral triangle.
Help ASAP if you get it right you get 100 points
Answer:
its e because i have done it before
Step-by-step explanation:
obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e obviously its e
Nolan set up the equipment shown in order to induce a current in a wire. A horizontal coil of wire on a spool is connected to 2 terminals of a meter with a needle, which can go from plus to minus. A hand holds a bar magnet oriented horizontally near the right end of the spool with the S pole toward the spool and the N pole toward the hand. Which best explains why no current is induced? The wire needs to be coiled less tightly. The wire needs to be straight, not coiled. The magnet needs to be moved through the coils of wire. The magnet needs to be held above the coils of wire.
Answer:
The answer is C on edge
Step-by-step explanation:
Took the test.
Answer:
The magnet needs to be moved through the coils of wire is correct
please solve for 50 points!!!
Step-by-step explanation:
I am assuming you want x? if so :
5x+12=6x-10
-x = -22
x =22
if u wanted angle J :
plug x back in
5(22)+12 = 122
subtract 180-122
J = 58°
Answer: person above me is correct
Step-by-step explanation:
5x+25=75 pls help appreciated
Answer:
x=10
Step-by-step explanation:
I guess solve for x
5x=50
x=10
Answer:
x=10
Step-by-step explanation:
Subtract to 25 from both sides
5x+25-25=75-25
so 75- 25 is 50
then ur left with 5x=50 so u divide because 5 is by x which means multipy so u do the opposite which is divding
5÷50 =10
A leasing firm claims that the mean number of miles driven annually, , in its leased cars is less than miles. A random sample of cars leased from this firm had a mean of annual miles driven. It is known that the population standard deviation of the number of miles driven in cars from this firm is miles. Assume that the population is normally distributed.
Is there support for the firm's claim at the level of significance?
Perform a one-tailed test.
null hypothesis?
alternative hypothesis?
type of test statistic?
value of the test statistic?
the p-value?
Can we support the leasing firm's claim that the mean number of miles driven annually is less than 12800 miles?
Complete question is;
A leasing firm claims that the mean number of miles driven annually, u , in its leased cars is less than 12800 miles. A random sample of 50 cars leased from this firm had a mean of 12499 annual miles driven. It is known that the population standard deviation of the number of miles driven in cars from this firm is 3140 miles. Is there support for the firm's claim at the 0.05 level of significance?
Perform a one-tailed test.
null hypothesis?
alternative hypothesis?
type of test statistic?
value of the test statistic?
the p-value?
Can we support the leasing firm’s claim that the mean number of miles driven annually is less than 12800 miles?
Answer:
A) Null hypothesis; μ ≥ 12800
Alternative hypothesis; μ < 12800
B) type of test statistic: z-score test
C) test statistic; z = -0.678
D) p - value = 0.2489
E) No, we can't support the leasing firms claim
Step-by-step explanation:
We are given;
Population mean; μ = 12800 miles
Sample mean; x¯ = 12499 miles
Sample size; n = 50
Population standard deviation; σ = 3140
Let's define the hypothesis;
Null hypothesis; μ ≥ 12800
Alternative hypothesis; μ < 12800
The alternative hypothesis is the claim.
Since sample size is greater than 30, we will use z-score test.
Formula for z-score;
z = (x¯ - μ)/(σ/√n)
z = (12499 - 12800)/(3140/√50)
z = -0.678
From online p-value from z-score calculator attached, using z = -0.678 with one tailed hypothesis and significance value of 0.05,we have;
p - value = P(z < -0.678) = 0.2489
The p-value is greater than the significance value, so we will fail to reject the null hypothesis and conclude that there is no sufficient information to support the leasing firm's claim
Liza gets paid $5.25 an hour to babysit her little cousins. Last weekend, she watched them for three hours on Friday, nine hours on Saturday, and seven hours on Sunday. How much money does her aunt owe her for her babysitting services?
A. $99.85
B. $99.75
C. $95.00
D. $63.00
hurry quick
Answer:
B. $99.75
Step-by-step explanation:
Friday=5.25*3=15.75
Saturday=5.25*9=47.25
Sunday=5.25*7=36.75
15.75+47.25+36.75=99.75
Answer:
B
Step-by-step explanation:
5.25 x 19 =
(10 x 5.25) + (9 x 5.25) =
52.5 + 47.25 =
$99.75
A watermelon that weighed 12 pounds cost $5.76. What was the cost per ounce of the watermelon?
Answer:
69.12
Step-by-step explanation:
12x5.76
Answer
69
Step-by-step explanation:
12×5.75=69
Daryl can jump 2 1/2 yards. sarah can jump 8 feet michell can jump 72 inches, witch statement is true.
Answer:
Where are the statements?
Step-by-step explanation:
Where are the statements?
Please this a really easy question. Does this mean I got an A on this test?! Please answer!!!!!!!!!!!!!!!
Answer:
yes it does. good job on your A.
Step-by-step explanation:
Answer:
Yes
Step-by-step explanation:
If y =
ya
x and x = -18, find y.
Answer:
y
=
3
√
−
2
a
x
y
=
−
3
√
−
2
a
x
Step-by-step explanation: