﻿ The probability that a student is not a swimmer is 1/5. The probability that out of 5 students exactly 4 is swimmer is : Kaysons Education

# The Probability That A Student Is Not A Swimmer Is 1/5. The Probability That Out Of 5 Students Exactly 4 Is Swimmer Is

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## Question

### Solution

Correct option is

Let p = probability that a student selected at random is a swimmer = 1 – 1/5 = 4/5.

n = number of students selected = 5

and       X = number of swimmers

Then X – B (np) when n = 5 and p = 4/5 probability that exactly 4 students are swimmer is

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