Question

From 6 different novels and 3 different dictionaries, 4 novels and 1 dictionary are to be selected and arranged in a row on a shell so that the dictionary is always in the middle.

The number of such arrangements is

(a) atleast 1000

(b) less than 500

(c) atleast 500 but less than 750

(d) atleast 750 but less than 1000

Answer 1

Correct option (a) atleast 1000

Explanation:

Given 6 different novels and 3 different dictionaries. 

Number of ways of selecting 4 novels from 6 novels is 

Number of ways of selecting 1 dictionary from 3 dictionaries is

.'. Total number of arrangement of 4 novels and 1 dictionary where dictionary is always in the middle, is