Probability Questions:

Question

A container contains 6 diesel engines. The company chooses 4 engines at random, and will not ship the container if any of the engines chosen are defective. Find the probability that a container will be shipped even though it contains 2 defectives if the sample size is 4.

Answer 1

we have 6 engines 2 defected and 4 ok,

 

p = all possible ways we choose 4 ok engines/ all possible ways we choose 4 from 6

 

selection of 4 from 4 = 4!/ (4! * 1!) = 1

selection of 4 from 6 = 6! / (4! * 2!) = 15

 

p = 1/15