28/1 ÷ 21/5 = 20/3 or 62/3
1.3333
21
the greatest common factor is 7, because 21 divided by 7 is 3, 28 divided by 7 is 4 and 56 divided by 7 is 8.
The answer is: 5/21 divided by 10/7 = 1/6
28/21 = 4/3 = 1 1/3
1/21/2
3.9298
20/28 + 21/28 = 41/28 or 1 and 13/28
1
10/21
3/5 divided by 1/7 is 21/5 or 4 and 1/5
7/8 ÷ 21 = 1/24