Subtract 12/9 from 72/7, Solve 10 2/7

Subtract 12/9 from 72/7

1^st number: 10 2/7, 2^nd number: 1 3/9

72/7 - 12/9 is 188/21.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 9 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 7 × 9 = 63,
72/7 = 72 × 9/7 × 9 = 648/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63
Subtract the two like fractions:
648/63 - 84/63 = 648 - 84/63 = 564/63
After reducing the fraction, the answer is 188/21
In mixed form: 820/21

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