Subtract 21/10 from 12/72, Solve 12/72

Subtract 21/10 from 12/72

1^st number: 12/72, 2^nd number: 2 1/10

12/72 - 21/10 is -29/15.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 10 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 72 × 5 = 360,
12/72 = 12 × 5/72 × 5 = 60/360
Likewise, for the 2nd fraction, since 10 × 36 = 360,
21/10 = 21 × 36/10 × 36 = 756/360
Subtract the two like fractions:
60/360 - 756/360 = 60 - 756/360 = -696/360
After reducing the fraction, the answer is -29/15

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