Question

If I spent 1/3 of my money on a pen and 4/7 on books how much do I have left?

Answer 1

1/3 = 7/21
4/7 = 12/21

21/21 - 19/21 = 2/21

Answer 2

1. Convert the two functions so that they have common denominators.

2. Add the two fractions.

3. Subtract the sum of the two fractions from one, (preferably the fractional form of one derived from the step one.)

4. Simplify, if possible.

Answer 3

Good answer, David, and better than mine. Sometimes I get lazy and just give a math answer.