Subtract 36/21 from 45/72, Solve 45/72

Subtract 36/21 from 45/72

1^st number: 45/72, 2^nd number: 1 15/21

45/72 - 36/21 is -61/56.

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,
45/72 = 45 × 7/72 × 7 = 315/504
Likewise, for the 2nd fraction, since 21 × 24 = 504,
36/21 = 36 × 24/21 × 24 = 864/504
Subtract the two like fractions:
315/504 - 864/504 = 315 - 864/504 = -549/504
After reducing the fraction, the answer is -61/56

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