Question

1. a school wants to estimate the average number of hours students sleep per night. a random sample of 36 students gives a mean of 7.5 hours and a standard - deviation of 1.9 hours. what is the standard error (se)?

a. 0.15
b. 0.35
c. 0.25
d. 0.28

Explanation:

Step1: Recall the formula for standard error

The formula for the standard error (SE) of the mean is $SE=\frac{s}{\sqrt{n}}$, where $s$ is the sample - standard deviation and $n$ is the sample size.

Step2: Identify the values of $s$ and $n$

We are given that $s = 1.5$ hours and $n=36$ students.

Step3: Calculate the standard error

Substitute the values into the formula: $SE=\frac{1.5}{\sqrt{36}}=\frac{1.5}{6}=0.25$.

Answer:

C. 0.25