Question

A store has $5$ white, $7$ red and $8$ black trousers. Four trousers are drawn one by one without replacement. The probability that all being white trousers is___

• A. $\frac{5}{1021}$
• B. $\frac{1}{969}$
• C. $\frac{5}{121}$
• D. $\frac{5}{127}$

Answer 1

Answer: (B)

$\frac{1}{969}$

Given:

Store has $5$ white, $7$ red and $8$ black trousers.

Hence total of $20$ trousers.

To find:

The probability that all being white trousers

We know,

$P\left(\text{getting all white trousers}\right)=\frac{5}{20}\times \frac{4}{19}\times \frac{3}{18}\times \frac{2}{17}=\frac{1}{969}$