Subtract 15/63 from 12/7, Solve 1 5/7

Subtract 15/63 from 12/7

1^st number: 1 5/7, 2^nd number: 15/63

12/7 - 15/63 is 31/21.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 63 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 7 × 9 = 63,
12/7 = 12 × 9/7 × 9 = 108/63
Likewise, for the 2nd fraction, since 63 × 1 = 63,
15/63 = 15 × 1/63 × 1 = 15/63
Subtract the two like fractions:
108/63 - 15/63 = 108 - 15/63 = 93/63
After reducing the fraction, the answer is 31/21
In mixed form: 110/21

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