Question

In a class of 100 students, 70 have taken Science, 60 have taken Mathematics, 40 have taken both Science and Mathematics. The number of students who have not taken Science or Mathematics or both Science and Mathematics, is equal to 

(a) 90 

(b) 10 

(c) 30 

(d) 20

Answer 1

Correct option is (b) 10

Explanation:

Total number of students = 100 

Number of students having Science = 70 

Number of students having Mathematics = 60 

Number of students having both Science and 

Mathematics = 40 

Now, number of students having Science only = 70 - 40 =30

Number of students having Mathematics only = 60 - 20 = 40

Thus, number of students having Science only, Mathematics only and both subjects = 30 + 20 + 40 =90 Number of students, who have not taken Science Mathematics both of the subjects 

=100 - 90 =10