Question

HELP PLEASE:

Answer 1

Answer: Mean of the sample proportion = 74.4

Standard deviation of the samnple proportion is 5.32.

Step-by-step explanation:

Given : A random sample of 120 is taken from a population of 10000.

Let n = 120

Also, from previous survey, it is believed that 62% of the population has an Instagram account.

i.e, population proportion : p = 0.62

Now , the mean of the sample proportin would be :

$\text{Mean}=\mu_{\hat{p}}=np\\\\=120\times0.62=74.4$

i.e. Mean of the sample proportion = 74.4

The standard deviation of the samnple proportion would be :

$\text{standard deviation}=\sigma_{\hat{p}}=\sqrt{np(1-p)}\\\\=\sqrt{120(0.62)(1-0.62)}\\\\=\sqrt{28.272}\\\\=5.31714208951\approx5.32$

Thus , the standard deviation of the samnple proportion is 5.32.