Subtract 70/42 from 12/27, Solve 12/27

Subtract 70/42 from 12/27

1^st number: 12/27, 2^nd number: 1 28/42

12/27 - 70/42 is -11/9.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 42 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 27 × 14 = 378,
12/27 = 12 × 14/27 × 14 = 168/378
Likewise, for the 2nd fraction, since 42 × 9 = 378,
70/42 = 70 × 9/42 × 9 = 630/378
Subtract the two like fractions:
168/378 - 630/378 = 168 - 630/378 = -462/378
After reducing the fraction, the answer is -11/9

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