Maths-
General
Easy
Question
Twelve students compete for a race. The number of ways in which first three places can be taken, is-
- 12 ! – 3
- 12
11 10
- 3 !
11 10
Hint:
There are only 3 prizes to be given to any 3 people out of 12. So if 1 person gets first prize, he will not be counted for second prize and so on....
The correct answer is: 12 11 10
The number of ways to select the winner of the first prize is 
The number of ways to select the winner of the second prize is 
(11, since one student is already given a prize)
The number of ways to select the winner of the third prize is 
(10, since two students are already given a prize)
Thus, total number of ways is ×× = 12 × 11 × 10 = 1320
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