Question

Andre has a bowl of chocolates where 70% of them are milk chocolate and the remaining 30% are

white chocolate. The bowl contains a total of 20 chocolates. If he pulls two chocolates randomly from
the bowl without replacement, which of the following is closest to the probability that they are both
white chocolate?
1) 15.4%
2) 12.0%
3) 9.0%
4) 7.9%​

Answer 1

4) 7.9%

Explanation:

Given:

% of milk chocolate = 70%

% of white chocolate = 30%

Total number of chocolate = 20

Number of milk chocolate:

`(70)/(100) * 20 = 14`

Number of white chocolate:

`(30)/(100) * 20 = 6`

From the calculations, we now know there are 14 milk chocolates and 6 white chocolates.

2 white chocolates are picked at random without replacement.

Probability first chocolate picked was white:
`(6)/(20) = 0.3`

Probability second chocolate picked was white:
`(5)/(19) = 0.2632`

To find probability that both of them are white chocolates, multiply probability of the first and second.

0.3 * 0.2632 = 0.07896

≈ 0.079

Convert to percentage by multiplying by 100.

0.079 * 100 = 7.9%

The probability that they are both

white chocolate is 7.9%