Question

The owner of a fish market has an assistant who has determined that the weights of catfish are normally distributed, with a mean of 3.2 pounds and a standard deviation of 0.8 pound. If a sample of 64 fish yields a mean of 3.4 pounds, what is probability of obtaining a sample mean this large or larger?

		0.4987
		0.0013
		0.0001
		0.0228

Answer 1

Solution :

Given that ,

mean = = 3.2

standard deviation = = 0.8

n = 64

= 3.2 and

= / n = 0.8 / 64 = 0.8 / 8 = 0.1

P( > 3.4) = 1 - P( < 3.4)

= 1 - P(( - ) / < (3.4 - 3.2) / 0.1)

= 1 - P(z < 2)

= 1 - 0.9772

= 0.0228

Probability = 0.0228