Question

Cream cheese is sold in cans that have a net weight of 8 ounces. The weights are normally distributed with a mean of 8.025 ounces and a standard deviation of 0.125 ounces. You take a sample of 36 cans. Compute the probability that the sample would have a mean 7.995 ounces or more.

(( NO HANDWRITING PLEASE ))

Answer 1

Solution :

Given that ,

mean = = 8.025

standard deviation = = 0.125

n = 36

= 8.025 and

= / n = 0.125 / 36

P( > 7.995) = 1 - P( < 7.995)

= 1 - P(( - ) / < (7.995 - 8.025) / 0.125 / 36 )

= 1 - P(z < -1.44)

    Using standard normal table,

P( > 7.995) = 1 - 0.0749 = 0.9251

Probability = 0.9251