Question

One day at St. Philip's High School, 1/2 of the pupils walked to school, 1/5 of the pupils came to school by bus, and the remaining 57 pupils came by car.

What fraction came to school by car?

Answer 1

The first thing to do is the make the denominators of the fractions the same.

5/10 of the pupils walked to school and 2/10 of the pupils came to school by bus.
5/10 + 2/10 = 7/10.
10/10 - 7/10 = 3/10.

3/10 of the pupils came to school by car.