Answer:
C. ± 2.326 years.
Step-by-step explanation:
We have the standard deviation for the sample. So we use the t-distribution to solve this question.
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
So it is z with a pvalue of 
, so ![z = 2.326/tex]Now, find the width of the interval[tex]W = z*\frac{\sigma}{\sqrt{n}}](https://tex.z-dn.net/?f=z%20%3D%202.326%2Ftex%5D%3C%2Fp%3E%3Cp%3E%3Cstrong%3ENow%3C%2Fstrong%3E%2C%20find%20the%20width%20of%20the%20interval%3C%2Fp%3E%3Cp%3E%5Btex%5DW%20%3D%20z%2A%5Cfrac%7B%5Csigma%7D%7B%5Csqrt%7Bn%7D%7D)
In which 
is the standard deviation of the population and n is the size of the sample.
In this question:
So
The correct answer is:
C. ± 2.326 years.
Answer:
Lily babysit for <u>less than 4 hours</u>.
Step-by-step explanation:
Given:
Lucy spends in a week babysitting for 4 hours.
Lily spends seven-eighths of 4 hours.
Now, to find whether Lily babysit for more than 4 hours or less than that.
Number of hours Lucy babysit = 4 hours.
So, to get the hours Lily babysit:
<em>On simplifying we get:</em>
<u><em>Thus, Lily spends </em></u>
<u><em> for babysitting which is less than 4 hours.</em></u>
Therefore, Lily babysit for less than 4 hours.
Hello! So Brittany plans to sell car magnets that she purchased at $7.50 and mark them up by 30%. To find the new price, we can multiply 7.50 * 1.30. When multiplied, it gives us 9.75. Brittany is planning to charge $9.75 for the car magnets.
{(3x)}^{2}-2(3x)(5)+{5}^{2}
−2(3x)(5)+5
2
{(3x-5)}^{2}
Answer:
x = 0.5
Step-by-step explanation:
hope this helps!
