Subtract 21/72 from 6/21, Solve 6/21

Subtract 21/72 from 6/21

6/21 - 21/72 is -1/168.

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

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 21 × 24 = 504,
6/21 = 6 × 24/21 × 24 = 144/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504
Subtract the two like fractions:
144/504 - 147/504 = 144 - 147/504 = -3/504
After reducing the fraction, the answer is -1/168

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