Question

when I add or subtract fractions first I must convert the denominators so they are common. Then I can add or subtract the?

Answer 1

Yes and the denominator will stay the same...for example: 8/10 + 1/10 = 9/10

Answer 2

Numerators.

Remember you have to convert the numerators as well.

Example:-   2/3 + 1/6

LCD = 6

2/3 becomes 2/3 * 2/2  = 4/6

4/6 + 1/6 = 5/6.