Subtract 7/14 from 70/21, Solve 3 7/21

Subtract 7/14 from 70/21

1^st number: 3 7/21, 2^nd number: 7/14

70/21 - 7/14 is 17/6.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 14 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
70/21 = 70 × 2/21 × 2 = 140/42
Likewise, for the 2nd fraction, since 14 × 3 = 42,
7/14 = 7 × 3/14 × 3 = 21/42
Subtract the two like fractions:
140/42 - 21/42 = 140 - 21/42 = 119/42
After reducing the fraction, the answer is 17/6
In mixed form: 25/6

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