First, find the greatest common factor, or the biggest number that goes into both 64 and 100. The GCF of 64 and 100 is 4 64 ÷ 4 = 16 100 ÷ 4 = 25 The reduced fraction is 16/25 Because there is no other number that goes into both 16 and 25, this is the most reduced you can get it. Therefore, 64/100 is reduced to 16/25