Question

A study on students drinking habits wants to determine the true average number of alcoholic drinks all uf underclassmen students have in a one week period. We know from preliminary studies that the standard deviation is around 2. 8. How many students should be sampled to be within 1. 5 drink of population mean with 90% probability?.

Answer 1

Answer: 16

Step-by-step explanation:

Standard deviation is 2

Margin error for the problem is 1

Probability 95%, that means thet the siginficance level α is 1 – p

α = 1 – 0.95 = 0.05

margin of error (ME) can be defined as follows

ME = Z(α/2) * standard deviation/ √n

Where n is the sample size

Z(0.05/2) = Z(0.025)

Using a z table Z = 1.96

Now, replacing in the equation and find n

1 = 1.96 * 2/ √n

1 = 3.92 / √n

√n = 3.92

n = 3.92^2

n = 15.36 = 16

i hope this work for you