In a school, 220 students offer Biology or Mathematics or both. 125 offer Biology and 110 mathematics. How many offer Biology but not Mathematics?
- 95
- 80
- 125
-
110
The correct answer is: D
Explanation
Hint: Represent the question in a venn diagram, such thatn(B ∩ M) = x
n(B) only = 125-x
n(M) only = 110-x
=> 125-x + 110-x + x = 220
=> x = 15.
n(B) only = 125 - 15 = 110