Question

There are 20 entries in a Chess Tournament. How many ways can they finish in first, second, and third place? A) 7 B) 28 C) 4 D) 14

Answer 1

b 28 there are 28 different posssiblilites.

Answer 2

The number of ways they can finish in first, second, and third place is:

6840

Explanation:

We know that choosing and arrangement of r items out of a total of n items is done by the method of permutation.

The formula is given by:

`n_P_r=(n!)/((n-r)!)`

Here we have to chose 3 entries and arrange them according to there ranks.

Hence, we have n=20 and r=3

Hence, the formula is given by:

`{20}_P_3=(20!)/((20-3)!)\\\\\\{20}_P_3=(20!)/(17!)\\\\\\{20}_P_3=20* 19* 18\\\\\\{20}_P_3=6840`