Question

In a group of 1000 people, there are 750 people who can speak Hindi and 400 who can speak English. Then number of persons who can speal Hindi only is *

Answer 1

Answer:

Correct option is

A

250

Let H and B denote the sets of those people who can speak Hindi and Bengali respectively. Given n(H∪B)=1000,n(H)=750,n(B)=400.

Now n(H∪B)=n(H)+n(B)−n(H∩B)

1000=750+400−n(H∩B)

⇒(H∩B)=150.

Hence 150 people can speak both Hindi and Bengali.

Number of people who can speak Bengali only

n(B∩H

′

)=n(B)−n(B∩H)

=400−150=250

Hence, 250 people can speak Bengali only.