In how many ways can 21 English and 19 Hindi books be placed in a row so that no two Hindi boo

English

Gujarati

Hindi

6.Permutation and Combination

easy

In how many ways can $21$ English and $19$ Hindi books be placed in a row so that no two Hindi books are together

A

$1540$

B

$1450$

C

$1504$

D

$1405$

Solution

(a) $ \bullet E \bullet E \bullet E \bullet …… \bullet E \bullet $

According to condition there are $22$ vacant places for Hindi books hence total number of ways are = $^{22}{C_{19}} = 1540$, {Since books are same}.

Standard 11

Mathematics

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