Subtract 49/21 from 70/18, Solve 3 16/18

Subtract 49/21 from 70/18

1^st number: 3 16/18, 2^nd number: 2 7/21

70/18 - 49/21 is 14/9.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
70/18 = 70 × 7/18 × 7 = 490/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
49/21 = 49 × 6/21 × 6 = 294/126
Subtract the two like fractions:
490/126 - 294/126 = 490 - 294/126 = 196/126
After reducing the fraction, the answer is 14/9
In mixed form: 15/9

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