In a group of 15 people; 7 can read French, 8 can read English while 3 of them can read neither of these two languages. The number of people who can read exactly one language is
Number of people who can read French, n(F) = 7
Number of people who can read English, n(E) = 8
Number of people who can read English or French of both is
n(E ∪ F) = 15 - 3 = 12
Number of people who can read both English and French,
n(E ∩ F) = n(F) + n(E) - n(E ∪ F)
n(E ∩ F) = 7 + 8 - 12 = 3
Number of people who can read exactly one language = 12 - 3 = 9
By Venn Diagram:
The correct option is B.