Subtract 42/9 from 72/7, Solve 10 2/7

Subtract 42/9 from 72/7

1^st number: 10 2/7, 2^nd number: 4 6/9

72/7 - 42/9 is 118/21.

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,
42/9 = 42 × 7/9 × 7 = 294/63
Subtract the two like fractions:
648/63 - 294/63 = 648 - 294/63 = 354/63
After reducing the fraction, the answer is 118/21
In mixed form: 513/21

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