Subtract 7/49 from 70/21, Solve 3 7/21

Subtract 7/49 from 70/21

1^st number: 3 7/21, 2^nd number: 7/49

70/21 - 7/49 is 67/21.

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,
70/21 = 70 × 7/21 × 7 = 490/147
Likewise, for the 2nd fraction, since 49 × 3 = 147,
7/49 = 7 × 3/49 × 3 = 21/147
Subtract the two like fractions:
490/147 - 21/147 = 490 - 21/147 = 469/147
After reducing the fraction, the answer is 67/21
In mixed form: 34/21

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