Subtract 5/21 from 21/72, Solve 21/72

Subtract 5/21 from 21/72

21/72 - 5/21 is 3/56.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504
Likewise, for the 2nd fraction, since 21 × 24 = 504,
5/21 = 5 × 24/21 × 24 = 120/504
Subtract the two like fractions:
147/504 - 120/504 = 147 - 120/504 = 27/504
After reducing the fraction, the answer is 3/56

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