Subtract 21/12 from 8/70, Solve 8/70

Subtract 21/12 from 8/70

1^st number: 8/70, 2^nd number: 1 9/12

8/70 - 21/12 is -229/140.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 12 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 70 × 6 = 420,
8/70 = 8 × 6/70 × 6 = 48/420
Likewise, for the 2nd fraction, since 12 × 35 = 420,
21/12 = 21 × 35/12 × 35 = 735/420
Subtract the two like fractions:
48/420 - 735/420 = 48 - 735/420 = -687/420
After reducing the fraction, the answer is -229/140

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