Q. 63.8( 4 Votes )

# In a textbook on mathematics there are three exercises A, B and C consisting of 12, 18 and 10 questions respectively. In how many ways can three questions be selected choosing one from each exercise?

Answer :

Given: three exercises A, B and C consisting of 12, 18 and 10 questions respectively.

To find: number of ways in which three questions be selected choosing one from each exercise.

Ways of selecting one question from exercise A:^{12}C_{1} (way of selecting one element from n number of elements.)

Ways of selecting one question from exercise B:^{18}C_{1}

Ways of selecting one question from exercise C:^{10}C_{1}

So number of ways of choosing one question from each exercise A ,B,C =^{12}C_{1} × ^{18}C_{1} × ^{10}C_{1}

=12 × 18 × 10

=2160

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