Question

There are 80 students in a class. If 65 students studied mathematics and 49 studied English language while a student did neither of the two subject

(1).How many students studied both subjects
(2). How many studied mathematics only

Answer 1

call it 79 students because one was in the cafeteria.

both + english alone + math alone = 79
call both = b
b + (49-b) + (65-b) = 79
114 - b = 79
b = 35
and
65 - b = 30 math alone