Since both numbers are even, a good starting point is to halve both numbers, so

72/100 = 36/50. Again these are both even, so halve them each again:

36/50 = 18/25 and this is as simple as you can get.

🙂

72/100 = 36/50 = 18/25

We have divided each numerator and denominator by 2 every time till we got 18/25.There is nothing common between 18 and 25 so simplest fraction is 18/25.

To simplify, get the greatest common factor of both.

72 = 1×72,2×36, 3×24, 4×18, 6×12, 8×9

100 = 1×100, 2×50, 4×25, 5×20, 10×10

Based from the above, their greatest common factor is 4.

Divide both by 4, you will get:

18/25

36/50 <--- both 72 and 100 are divisible by 2 18/25 <--- again, both 36 and 50 are divisible by 2. simplest terms, can't divide any further