Answer:
Mean = 21.3
Standard Deviation = 2.48
Step-by-step explanation:
We are given the following in the question:
p = 71% = 0.71
Sample size, n = 30
We have to find the mean and the standard deviation of those that wear glasses.
[tex]\text{Mean} = np\\=30(0.71)\\=21.3[/tex]
Thus, the mean of those who wear glasses is 21.3
[tex]\text{Standard deviation} = \sqrt{npq}\\=\sqrt{np(1-p)}\\=\sqrt{30\times 0.71\times (1-0.71)}\\=2.48[/tex]
Thus, the standard deviation of those who wear glasses is 2.48
