Subtract 28/72 from 21/49, Solve 21/49

Subtract 28/72 from 21/49

21/49 - 28/72 is 5/126.

Find the least common denominator or LCM of the two denominators:
LCM of 49 and 72 is 3528

Next, find the equivalent fraction of both fractional numbers with denominator 3528
For the 1st fraction, since 49 × 72 = 3528,
21/49 = 21 × 72/49 × 72 = 1512/3528
Likewise, for the 2nd fraction, since 72 × 49 = 3528,
28/72 = 28 × 49/72 × 49 = 1372/3528
Subtract the two like fractions:
1512/3528 - 1372/3528 = 1512 - 1372/3528 = 140/3528
After reducing the fraction, the answer is 5/126

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