Answer:
Mean = 0.45
Standard deviation = 0.04035
Explanation:
This is actually a very simple problem.
The question gives us the report that 45% of the teenagers in the age bracket own smartphones.
P = mean = 45%
Therefore the mean is 0.45.
I will go ahead to help you calculate the standard deviation.
√p(1-p)/n
n = 152
P = 0.45
√0.45(1-0.45)/152
= √0.45(0.55)/152
= √0.2475/152
= √ 0.001628
= 0.04035