SOLUTION: The average diameter of sand dollars on a certain island is 4.00 centimeters with a standard deviation of 0.60 centimeters. If 16 sand dollars are chosen at random for a collection

Question 1089629: The average diameter of sand dollars on a certain island is 4.00 centimeters with a standard deviation of 0.60 centimeters. If 16 sand dollars are chosen at random for a collection, find the probability that the average diameter of those sand dollars is more than 3.85 centimeters. Assume that the variable is normally distributed.
a. 0.659

b. 0.780

c. 0.341

d. 0.841

Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
z=(xbar-mean)/sigma/sqrt(n)
z>-0.15/0.60/sqrt(16)=-0.15*4/0.60
z>= -1
That is 0.8413
D.
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