Subtract 4/12 from 30/70, Solve 30/70

Subtract 4/12 from 30/70

30/70 - 4/12 is 2/21.

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,
30/70 = 30 × 6/70 × 6 = 180/420
Likewise, for the 2nd fraction, since 12 × 35 = 420,
4/12 = 4 × 35/12 × 35 = 140/420
Subtract the two like fractions:
180/420 - 140/420 = 180 - 140/420 = 40/420
After reducing the fraction, the answer is 2/21

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