Question

At a certain conference of 100 people there are 29 Indian women and 23 Indian men of these Indian people four doctors and 24 are either men or doctors. There are no foreign doctors how many foreigners and women doctors are attending the conference!?

Answer 1

Total people = T=100
Indian women=A=29
Indian men=B=23

Total indians=Indian men+Indian women=AUB=23+29=52

Hence,
Number of foreigners= Total-number of indians= 100-52=48.

Hence, number of foreigners = 48.

There are no foreign doctors.
All doctors are indians.
So,, number of doctors=D=4
Given, either men or doctor=24.

Either men or doctor means BUD=24
We know,
B U D=B+D - B Π D
( Π means intersection)
So, BΠD= 23+4-24=3
So, men doctors= 3.
So, women doctors = D-men doctors= 4-3=1.

So, number of foreigners=48 and women doctors =1