Subtract 15/14 from 21/63, Solve 21/63

Subtract 15/14 from 21/63

1^st number: 21/63, 2^nd number: 1 1/14

21/63 - 15/14 is -31/42.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 14 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 63 × 2 = 126,
21/63 = 21 × 2/63 × 2 = 42/126
Likewise, for the 2nd fraction, since 14 × 9 = 126,
15/14 = 15 × 9/14 × 9 = 135/126
Subtract the two like fractions:
42/126 - 135/126 = 42 - 135/126 = -93/126
After reducing the fraction, the answer is -31/42

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