Subtract 2/7 from 21/12, Solve 1 9/12

Subtract 2/7 from 21/12

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

21/12 - 2/7 is 41/28.

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,
21/12 = 21 × 7/12 × 7 = 147/84
Likewise, for the 2nd fraction, since 7 × 12 = 84,
2/7 = 2 × 12/7 × 12 = 24/84
Subtract the two like fractions:
147/84 - 24/84 = 147 - 24/84 = 123/84
After reducing the fraction, the answer is 41/28
In mixed form: 113/28

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