Question

The amount of syrup that people put on their pancakes is normally distributed with mean 80mL and a standard deviation of 12 mL. Suppose that 16 randomly selected people are observed pouring syrup on their pancakes.

For the group of randomly selected 16 people. What is the probability that the average amount of syrup is between 75.5 mL and 84.5mL?

Answer 1

Solution :

Given that,

mean = = 80

standard deviation = = 12

= / n = 12 / 16 = 3

= P[(75.5 - 80) / 3< ( - ) / < (84.5 - 80) / 3)]

= P(-1.5 < Z < 1.5)

= P(Z < 1.5) - P(Z < -1.5)

= 0.9332 - 0.0668

= 0.8664

Probability = 0.8664