Question

In a class of 16student do Geography 18 do Chemistry 5 do both and 3 do neither.How many student are in the class

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Answer 1

x = 42.

Explanation:

Let number of students in the class = x

let N(G) = 16

let N(C)= 18

Let N(G intersection C) = 5

Let N(G' intersection C') = 3

i). Students in the class

N(G) + N(C) + N(G intersectionC) + N(G' intersectionC') = X

16 + 18 + 5 + 3 = x

42 = x.

therefore the total number of students in the class is 42.