In a class of 50 students, 3/5 went away do painting, 1/5 went to play in the field. How many students are left in the classroom?  Pick one.
A) 20  B) 30  C) 5  D) 8  E) 10

Rationale: 3 / 5 + 1 / 5 are the students who have left the classroom 3 / 5 + 1 / 5 = ( 3 + 1 ) / 5 , since denominator is same for both fractions = 4 / 5 remaining students in the classroom = 1 - 4 / 5 = 5 / 5 - 4 / 5 = ( 5 - 4 ) / 5 = 1 / 5 1 / 5 of 50 = 10 ans : e
Answer: E