Subtract 12/18 from 49/21, Solve 2 7/21

Subtract 12/18 from 49/21

1^st number: 2 7/21, 2^nd number: 12/18

49/21 - 12/18 is 5/3.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
49/21 = 49 × 6/21 × 6 = 294/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
12/18 = 12 × 7/18 × 7 = 84/126
Subtract the two like fractions:
294/126 - 84/126 = 294 - 84/126 = 210/126
After reducing the fraction, the answer is 5/3
In mixed form: 12/3

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