Subtract 4/15 from 49/21, Solve 2 7/21

Subtract 4/15 from 49/21

1^st number: 2 7/21, 2^nd number: 4/15

49/21 - 4/15 is 31/15.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
49/21 = 49 × 5/21 × 5 = 245/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
4/15 = 4 × 7/15 × 7 = 28/105
Subtract the two like fractions:
245/105 - 28/105 = 245 - 28/105 = 217/105
After reducing the fraction, the answer is 31/15
In mixed form: 21/15

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