Question

An inspector must select three tests to preform in a certain order on a manufactured part. He has a choice of seven tests how many different ways can he perform three tests

Answer 1

Therefore the inspector can perform three tests in 35 different ways.

Explanation:

i) It is given that there is a total of seven tests that the inspector can perform.

ii) it is also given that the inspector needs to select or choose three tests only out of the seven.

iii) therefore this is a Combination problem.

iv) therefore the number of combinations or selections possible is given by

`\binom{7}{3} = (7!)/((3!)(7 - 3)!) = (7!)/((3!)(4!)) = (42 * 120)/(6 * 24) = (42 * 20)/(24) = (21 * 10)/(6) = (7 * 10)/(2) = 35`

Therefore the inspector can perform three tests in 35 different ways.