Question

A consumer organization estimates that over a​ 1-year period 19​% of cars will need to be repaired​ once, 7​% will need repairs​ twice, and 2​% will require three or more repairs. What is the probability that a car chosen at random will need ​a) no​ repairs? ​b) no more than one​ repair? ​c) some​ repairs?

Answer 1

Answer:

The answer are:

A) 72%

B) 91%

C) 9%

Explanation:

The total amount of cars that will need some type of repair is 28%; 19% will need to be repaired once + 7% will need to be repaired twice + 2% will need to be repaired more than two times.

The amount of cars that wouldn´t need any type of repairs is the total amount of cars minus the percentage that need some type of repair; 100% - 28% = 72%.

The amount of cars that will need no repairs or only one repair is the total amount of cars minus the percentage that need more than one of repair; 100% - (7% + 2%) = 91%.

The amount of cars that need some repairs is the sum of those cars that need two repairs plus those that need three or more repairs; 7% + 2% = 9%