Question

The output of a process is stable and normally distributed. If the process mean equals 23.5, the percentage of output expected to be less than or equal to the mean: a. is 50%. b. is greater than 75%. c. cannot be determined without knowing the standard deviation value. d. is less than 25%

Answer 1

Option a) 50% of output expected to be less than or equal to the mean.

Explanation:

We are given the following in the question:

The output of a process is stable and normally distributed.

Mean = 23.5

We have to find the percentage of output expected to be less than or equal to the mean.

Mean of a normal distribution.

• The mean of normal distribution divides the data into exactly two equal parts.

• 50% of data lies to the right of the mean.

• 50% of data lies to the right of the mean

Thus, by property of normal distribution 50% of output expected to be less than or equal to the mean.