Subtract 20/12 from 18/70, Solve 18/70

Subtract 20/12 from 18/70

1^st number: 18/70, 2^nd number: 1 8/12

18/70 - 20/12 is -148/105.

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,
18/70 = 18 × 6/70 × 6 = 108/420
Likewise, for the 2nd fraction, since 12 × 35 = 420,
20/12 = 20 × 35/12 × 35 = 700/420
Subtract the two like fractions:
108/420 - 700/420 = 108 - 700/420 = -592/420
After reducing the fraction, the answer is -148/105

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