Subtract 15/12 from 49/21, Solve 2 7/21

Subtract 15/12 from 49/21

1^st number: 2 7/21, 2^nd number: 1 3/12

49/21 - 15/12 is 13/12.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
49/21 = 49 × 4/21 × 4 = 196/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84
Subtract the two like fractions:
196/84 - 105/84 = 196 - 105/84 = 91/84
After reducing the fraction, the answer is 13/12
In mixed form: 11/12

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