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Question
Twelve students complete in a race. In how many ways first three prizes be given?
Solution
Number of competitors in the race = 12
Number of competitors who can come first in the race = 12
Number of competitors who can come second in the race = 11 (as one competitor has already come first in the race)
Number of competitors who can come third in the race = 10
∴ Total number of ways of awarding the first three prizes = 12\[\times\]11\[\times\]10 = 1320
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