Description
An average number of hours that a kid spends per day working At a computer is3.5 hours with a STDV of 0.9 hours.Whats the probability that a randomly selected sample of 12 kids tospend an average of more than 3.8 hours per day working on a computer?
Explanation & Answer
xbar =3.8
mu =3.5
sigma =0.9
n =12
z = (3.8-3.5)/(0.9/sqrt(12)) = 0.3 *sqrt(12)/0.9 = 1.15
P(z> 1.45) =0.1251
Answer: 0.1251 or 12.51%