Subtract 4/56 from 20/72, Solve 20/72

Subtract 4/56 from 20/72

20/72 - 4/56 is 13/63.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 56 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504
Likewise, for the 2nd fraction, since 56 × 9 = 504,
4/56 = 4 × 9/56 × 9 = 36/504
Subtract the two like fractions:
140/504 - 36/504 = 140 - 36/504 = 104/504
After reducing the fraction, the answer is 13/63

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