## Question

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

### Solution

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* (*n*, *p*) when *n* = 5 and *p* = 4/5 probability that exactly 4 students are swimmer is

#### SIMILAR QUESTIONS

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