Subtract 4/5 from 49/21, Solve 2 7/21

Subtract 4/5 from 49/21

1^st number: 2 7/21, 2^nd number: 4/5

49/21 - 4/5 is 23/15.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 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 5 × 21 = 105,
4/5 = 4 × 21/5 × 21 = 84/105
Subtract the two like fractions:
245/105 - 84/105 = 245 - 84/105 = 161/105
After reducing the fraction, the answer is 23/15
In mixed form: 18/15

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