Subtract 12/72 from 24/21, Solve 1 3/21

Subtract 12/72 from 24/21

1^st number: 1 3/21, 2^nd number: 12/72

24/21 - 12/72 is 41/42.

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,
24/21 = 24 × 24/21 × 24 = 576/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
12/72 = 12 × 7/72 × 7 = 84/504
Subtract the two like fractions:
576/504 - 84/504 = 576 - 84/504 = 492/504
After reducing the fraction, the answer is 41/42

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