19 7/9 - 7 13/15
Make them improper fractions
178/9 - 118/15
Multiply the top and bottom of the left fraction by 15
2670/135 - 118/15
Multiply the top and bottom of the right fraction by 9
2670/135 - 1062/135
The denominators (the bottoms) are the same now, so you can do this
(2670 - 1062) / 135
1608 / 135
Let's reduce. Factor the 1608 like this
1608 = 2 * 2 * 2 * 3 * 67
Factor the 135 like this
135 = 3 * 3 * 3 * 5
The only thing 2 * 2 * 2 * 3 * 67 and 3 * 3 * 3 * 5 have in common is a 3. That 3 is all we can factor out of 1608 / 135. Factor the 3 out like this
1608 / 135 = 536 / 45
If you want to return it to a mixed fraction, then do this
536 / 45 = 11 41/45
The answer is 11 41/45