Subtract 18/72 from 24/21, Solve 1 3/21

Subtract 18/72 from 24/21

1^st number: 1 3/21, 2^nd number: 18/72

24/21 - 18/72 is 25/28.

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,
18/72 = 18 × 7/72 × 7 = 126/504
Subtract the two like fractions:
576/504 - 126/504 = 576 - 126/504 = 450/504
After reducing the fraction, the answer is 25/28

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