Question

A box contains 2 dozen pairs of contact lenses ,of which 8 pairs are tinted. A pair of contact lenses is drawn at random from the box.Find the probability that it is not tinted.What is the answer:2/3 2/5

Answer 1

`(2)/(3).`

Explanation:

It is given that a box contains 2 dozen pairs of contact lenses ,of which 8 pairs are tinted.

1 dozen = 12 units

Total pairs of contact lenses
`=2* 12 = 24`

Tinted pairs of contact lenses = 8

Pairs of contact lenses not tinted = 24 - 8 = 16

If a pair of contact lenses is drawn at random from the box, then we need to find the probability that it is not tinted.

`P(\text{Not tinted})=\frac{\text{Pairs of contact lenses not tinted}}{\text{Total pairs of contact lenses}}`

`P(\text{Not tinted})=(16)/(24)`

`P(\text{Not tinted})=(2)/(3)`

Therefore, the required probability is
`(2)/(3).`