Subtract 9/7 from 81/12, Solve 6 9/12

Subtract 9/7 from 81/12

1^st number: 6 9/12, 2^nd number: 1 2/7

81/12 - 9/7 is 153/28.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
81/12 = 81 × 7/12 × 7 = 567/84
Likewise, for the 2nd fraction, since 7 × 12 = 84,
9/7 = 9 × 12/7 × 12 = 108/84
Subtract the two like fractions:
567/84 - 108/84 = 567 - 108/84 = 459/84
After reducing the fraction, the answer is 153/28
In mixed form: 513/28

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