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

Subtract 70/21 from 4/18

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

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

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,
4/18 = 4 × 7/18 × 7 = 28/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
70/21 = 70 × 6/21 × 6 = 420/126
Subtract the two like fractions:
28/126 - 420/126 = 28 - 420/126 = -392/126
After reducing the fraction, the answer is -28/9

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