Question

A sample of 3 different calculators is randomly selected from a group containing 17 that are bad and 36 that are good. What is the probability that all three calculators are good?

Answer 1

Probability of all 3  calculators being good = 0.971.

Step-by-step explanation:

We have , A sample of 3 different calculators is randomly selected from a group containing 17 that are bad and 36 that are good. In order to calculate that all 3 randomly selected calculators are good , let's calculate probability of all 3 being bad and subtracting value by 1. i.e. Probability of all 3 being good = 1 - Probability of all 3 being bad

⇒  Probability of all 3 being bad  = $\frac{17}{53}$×$\frac{17}{53}$×$\frac{17}{53}$ =  4193/148877

∴Probability of all 3 being good = 1 - Probability of all 3 being bad

⇒ $1 - \frac{4193}{148877}$

⇒$\frac{144684}{148877}$

∴Probability of all 3  calculators being good = 0.971.