Subtract 4/18 from 70/21, Solve 3 7/21

Subtract 4/18 from 70/21

1^st number: 3 7/21, 2^nd number: 4/18

70/21 - 4/18 is 28/9.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
70/21 = 70 × 6/21 × 6 = 420/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
4/18 = 4 × 7/18 × 7 = 28/126
Subtract the two like fractions:
420/126 - 28/126 = 420 - 28/126 = 392/126
After reducing the fraction, the answer is 28/9
In mixed form: 31/9

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