Subtract 21/63 from 75/72, Solve 1 3/72

Subtract 21/63 from 75/72

1^st number: 1 3/72, 2^nd number: 21/63

75/72 - 21/63 is 17/24.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 63 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
75/72 = 75 × 7/72 × 7 = 525/504
Likewise, for the 2nd fraction, since 63 × 8 = 504,
21/63 = 21 × 8/63 × 8 = 168/504
Subtract the two like fractions:
525/504 - 168/504 = 525 - 168/504 = 357/504
After reducing the fraction, the answer is 17/24

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