Subtract 42/48 from 20/70, Solve 20/70

Subtract 42/48 from 20/70

20/70 - 42/48 is -33/56.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 48 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 70 × 24 = 1680,
20/70 = 20 × 24/70 × 24 = 480/1680
Likewise, for the 2nd fraction, since 48 × 35 = 1680,
42/48 = 42 × 35/48 × 35 = 1470/1680
Subtract the two like fractions:
480/1680 - 1470/1680 = 480 - 1470/1680 = -990/1680
After reducing the fraction, the answer is -33/56

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