Question

The weights of ice cream cartons are normally distributed with a mean weight of 7 ounces and a standard deviation of 0.5 ounce what is the probability that a randomly selected carton has a weight greater than 7.14 ounces?

Answer 1

0.3897

Explanation:

Using the normal distribution we can find z value with the mean and standard deviation as follows.

Let x be the weight of an ice cream carton

z = (x - mean)/standard deviation

z = (7.14 - 7)/0.5

z = 0.28

Using z tables for normal distribution, for z = 0.28, we have an area under the curve of 0.6103. Since we want to know the probability for 7.14 ounces or more, we have to substract from

p = 1- 0.6103

p = 0.3897