Question

A quality-control engineer samples 100 items manufactured by a certain process, and finds that 15 of them are defective. True or False:

a) The probability that an item produced by this process is defective is 0.15.
b) The probability that an item produced by this process is defective is likely to be close to 0.15, but not exactly equal to 0.15.

Answer 1

Answer: b) The probability that an item produced by this process is defective is likely to be close to 0.15, but not exactly equal to 0.15.

Explanation:

Given that:

Number of samples = 100

Number of defective samples = 15

Proportion =number defective samples / total samples

P = 15 / 100 = 0.15

Hence, the probability that an item produces is defective is 0.15.

However, due to sampling Variations, the probability will be corrected for these variations. Hence, probability that an item produced by this process is defective is likely to be close to 0.15, but not exactly equal to 0.15.