Subtract 20/70 from 3/12, Solve 3/12

Subtract 20/70 from 3/12

3/12 - 20/70 is -1/28.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 12 × 35 = 420,
3/12 = 3 × 35/12 × 35 = 105/420
Likewise, for the 2nd fraction, since 70 × 6 = 420,
20/70 = 20 × 6/70 × 6 = 120/420
Subtract the two like fractions:
105/420 - 120/420 = 105 - 120/420 = -15/420
After reducing the fraction, the answer is -1/28

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