Subtract 7/15 from 70/21, Solve 3 7/21

Subtract 7/15 from 70/21

1^st number: 3 7/21, 2^nd number: 7/15

70/21 - 7/15 is 43/15.

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,
70/21 = 70 × 5/21 × 5 = 350/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
7/15 = 7 × 7/15 × 7 = 49/105
Subtract the two like fractions:
350/105 - 49/105 = 350 - 49/105 = 301/105
After reducing the fraction, the answer is 43/15
In mixed form: 213/15

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