Question

It is noted that 8% of kaplan students are left handed. If 20 students are randomly selected, how do you calculate the probability that none of them are left handed?

Answer 1

P(20 right handed students) `=0.18869`

This is a probability of about `18.9%`

Explanation:

P(left handed) = `8% = 0.08`

P(right handed) = 1 - P(left handed) = `1-0.08 = 0.92`

For none of 20 students to be left handed, means they must all be right handed.

`P(R R R R......R R R)" "larr` 20 times

=`0.92 xx 0.92 xx 0.92 xx xx 0.92" "larr` 20 times

=`0.92^20`

=`0.18869`

This is a probability of about `18.9%`