Subtract 15/27 from 49/21, Solve 2 7/21

Subtract 15/27 from 49/21

1^st number: 2 7/21, 2^nd number: 15/27

49/21 - 15/27 is 16/9.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 21 × 9 = 189,
49/21 = 49 × 9/21 × 9 = 441/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
15/27 = 15 × 7/27 × 7 = 105/189
Subtract the two like fractions:
441/189 - 105/189 = 441 - 105/189 = 336/189
After reducing the fraction, the answer is 16/9
In mixed form: 17/9

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