How do you solve 3 1/4 - 1 7/8 step by step?

1 3/8.

Step-by-step explanation:

3 1/4 - 1 7/8

First convert to improper fractions:

3 1/4 = (3*4) + 1 / 4 = 13/4.

1 7/8 = (1 * 8) + 7 / 8 = 15/8. So we have:

13/4 - 15/8

The Lowest Common Multiple of 4 and 8 is 8 so we convert 13/4 to eighth's

13 / 4 = 13*2 / 4 * 2 = 26/8

Finally: we have

26/8 - 15/8 = (26 - 15) / 8

= 11 / 8

= 1 3/8 (answer)