A group of people are asked about their favourite subject when they were in school. The number of people who said they liked math was 216 , the number who say they liked science was  139  and the number who say they  like  math OR science  is 300 . How many people like both  math AND like science?

2 years ago

Answered By Majid B

A: set of people who said they liked math

B: set of people who said they liked science

n(A)= 216

n(B)=139

n(AUB)=300

n(AUB)=n(A)+n(B)-n(A∩B)

300=216+139-n(A∩B)

n(A∩B)=216+139-300=55

Then the number of people who like both math AND science is 55.

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