Subtract 70/21 from 2/18, Solve 2/18

Subtract 70/21 from 2/18

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

2/18 - 70/21 is -29/9.

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,
2/18 = 2 × 7/18 × 7 = 14/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
70/21 = 70 × 6/21 × 6 = 420/126
Subtract the two like fractions:
14/126 - 420/126 = 14 - 420/126 = -406/126
After reducing the fraction, the answer is -29/9

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