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

Subtract 21/49 from 49/21

1^st number: 2 7/21, 2^nd number: 21/49

49/21 - 21/49 is 40/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147

Next, find the equivalent fraction of both fractional numbers with denominator 147
For the 1st fraction, since 21 × 7 = 147,
49/21 = 49 × 7/21 × 7 = 343/147
Likewise, for the 2nd fraction, since 49 × 3 = 147,
21/49 = 21 × 3/49 × 3 = 63/147
Subtract the two like fractions:
343/147 - 63/147 = 343 - 63/147 = 280/147
After reducing the fraction, the answer is 40/21
In mixed form: 119/21

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