Subtract 9/7 from 40/12, Solve 3 4/12

Subtract 9/7 from 40/12

1^st number: 3 4/12, 2^nd number: 1 2/7

40/12 - 9/7 is 43/21.

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,
40/12 = 40 × 7/12 × 7 = 280/84
Likewise, for the 2nd fraction, since 7 × 12 = 84,
9/7 = 9 × 12/7 × 12 = 108/84
Subtract the two like fractions:
280/84 - 108/84 = 280 - 108/84 = 172/84
After reducing the fraction, the answer is 43/21
In mixed form: 21/21

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