Question

Henry has 3 black shirts and 7 blue shirts in his wardrobe. Two shirts are drawn without replacement from the wardrobe. What is the probability that both of the shirts are black?

Answer 1

Since there are three black shirts and 7 blue shirts, he has a 3/10 chance of picking a black.

Answer 2

The probability that both of the shirts are black is
`(1)/(15)`

Explanation:

Given : Henry has 3 black shirts and 7 blue shirts in his wardrobe. Two shirts are drawn without replacement from the wardrobe.

To find : What is the probability that both of the shirts are black?

Solution :

Number of black shirts = 3

Number of blue shirt = 7

Total number shirts = 3+7=10

The probability that first shirts is black is
`(3)/(10)`

Two shirts are drawn without replacement from the wardrobe.

Number of black shirt left = 2

Total shirts = 9

The probability that second shirts is black is
`(2)/(9)`

So, The probability that both of the shirts are black is

`P=(3)/(10)*(2)/(9)`

`P=(6)/(90)`

`P=(1)/(15)`