edited by
631 views
0 votes
0 votes

A dinner party is to be fixed for a group consisting of $100$ persons. In this party, $50$ persons do not prefer fish, $60$ prefer chicken and $10$ do not prefer either chicken or fish. The number of persons who prefer both fish and chicken is:

  1. $10$
  2. $20$
  3. $30$
  4. $40$
edited by

1 Answer

1 votes
1 votes

Answer is B

$n(A\cup B) = n(A)+n(B)-n(A\cap B)$

n(persons who do not prefer either chicken or fish) = n(persons who do not prefer chicken) + n(persons who do not prefer fish) – n(persons who do not prefer both chicken and fish)

n(persons who do not prefer either chicken or fish) = (100 – 60) + 50 – 10 = 80

ׯ The number of persons who prefer both fish and chicken = 100 – 80 = 20

 

Answer:

Related questions

0 votes
0 votes
1 answer
1
Lakshman Bhaiya asked Apr 3, 2020
632 views
If $ \ Sinx+Sin^{2} x=1$ then $ \ Cos^{8}x+ 2 \ Cos^{6} x+ \ Cos^{4} x$ equals to :$0$$-1$$1$$2$
3 votes
3 votes
1 answer
2
Lakshman Bhaiya asked Apr 3, 2020
905 views
A two digit number is such that the product of the digits is $8$. When $18$ is added to the number, the digits are reversed. The number is :$18$$24$$81$$42$
0 votes
0 votes
4 answers
3
Lakshman Bhaiya asked Apr 3, 2020
1,023 views
In a swimming-pool $90$ m by $40$ m, $150$ men take a dip. If the average displacement of water by a man is $8$ cubic metres, what will be rise in water level ?$30$ cm$33...
0 votes
0 votes
2 answers
4
Lakshman Bhaiya asked Apr 3, 2020
893 views
A conical tent is to accommodate $10$ persons. Each person must have $6\;m^{2}$ space to sit and $30\;m^{3}$ of air to breath. What will be height of cone ?$37.5\;m$$150\...
0 votes
0 votes
1 answer
5