Here are some questions you can do to test if you understand it properly.
2/3 x 5/8
7/9 + 2/7
4/10 - 3/10
1/3 / 4/15
8/9 + 4/5
2/4 / 5/16
9/10 x 3/5
4/8 - 7/9
72/100 x 85
60/100 x 32
45/100 x 88
78/100 x 90
21/100 x 12
85/100 x 40
25/100 x 54
1/100 x 42
You can contact our emails if you would like to get feedback to them. You can also show how you calculated them by taking pictures and sending it to us too.