Others Maths Puzzle Numerical Ability Permutation and Combination

In how many ways can 21 books on English and 19 books on Hindi be placed in a row on a shelf so that two books on Hindi may not be together?

a. 3990
b. 1540
c. 1995
d. 3672

Read Solution (Total 4)

there are 22 books on english.hence there can be 22 places possible for hindi books.
therefore 19 places from 22 places can be selected in 22C19 ways i.e.22C3 ways.
hence 22*21*20/3*2*1=1540
10 years agoHelpfull: Yes(4) No(4)

ans is 1540
10 years agoHelpfull: Yes(0) No(4)
why we are not considering about the order of arrangement of books???
10 years agoHelpfull: Yes(0) No(1)
21c3=21*20*19/3*2*1
1330
8 years agoHelpfull: Yes(0) No(0)

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