Question

In a town of 10,000 families it was found that 40% families buy newspaper A, 20% families buy newspaper B, 10% families buy newspaper C, 5% families buy A and B, 3% buy B and C and 4% buy A and C. If 2% families buy all the three newspapers. Find
(a) The number of families which buy newspaper A only.
(b) The number of families which buy none of A, B and C

Answer 1

Answer :
       Total Number of Families (N) = 10,000
 a) Number of families which buy Newspaper A = 40%*N +5%N + 4%N +2%N
                        = 40/100*10000 + 5/100*10000 + 4*100*10000 + 2/100*10000
                       = 10000/100(40+5+4+2) = 100(51) = 5100

b) Number of Families which doesn't buy Any NewsPaper = (100 -    (40+20+10+5+3+4+2))%N
= (100 - 84)%N
   = 16%N
   = 16/100*10000 = 16*100= 1600

Hope This helps You!!

Thank You!!

Answer 2

The answer is given below :)