Subtract 15/54 from 49/21, Solve 2 7/21

Subtract 15/54 from 49/21

1^st number: 2 7/21, 2^nd number: 15/54

49/21 - 15/54 is 37/18.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 21 × 18 = 378,
49/21 = 49 × 18/21 × 18 = 882/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
15/54 = 15 × 7/54 × 7 = 105/378
Subtract the two like fractions:
882/378 - 105/378 = 882 - 105/378 = 777/378
After reducing the fraction, the answer is 37/18
In mixed form: 21/18

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