This is a question that has been asked by my teacher who is helping me prepare for the Common Admission Test conducted in India for admission into postgraduate management programmes of Indian universities.
Question: If the boys of a class wear one shirt each, 4 shirts remain extra. If each boy wears 2 shirts each, two boys are left shirtless. How many boys are there in the class?
I know that the answer is 8 boys. I arrived at the answer by trial and error. But I want a definite approach which can help arrive at the right answer quickly.