226k views
2 votes
In a survey one-forth like cake only and 20 didn't like cake at all. Also 50% children like ice cream but 12 like none of them.How many like both?

1 Answer

3 votes

Answer:

2

Explanation:

Let x represent the total number of people. Let C represent those that like cake and let I represent those that like ice cream. Given:

C = (1/4)x = 0.25x, I = 0.5x, (C ∪ I)' = 12, C' = 20

Therefore:

C ∩ I' = C' - (C ∪ I)' = 20 - 12 = 8

C ∩ I = C - C ∩ I' = 0.25x - 8

C' ∩ I = I - C ∩ I = 0.5x - (0.25x - 8) = 0.25x + 8

The total students = (C ∩ I) + (C' ∩ I) + (C ∩ I') + (C ∪ I)'

x = 0.25x - 8 + 0.25x + 8 + 8 + 12

x = 0.5x + 8 + 12

x = 0.5x + 20

0.5x = 20

x = 40

Students that liked both = C ∩ I = 0.25(40) - 8 = 2

User Chantastic
by
8.1k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories