Subtract 42/70 from 18/48, Solve 18/48

Subtract 42/70 from 18/48

18/48 - 42/70 is -9/40.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 48 × 35 = 1680,
18/48 = 18 × 35/48 × 35 = 630/1680
Likewise, for the 2nd fraction, since 70 × 24 = 1680,
42/70 = 42 × 24/70 × 24 = 1008/1680
Subtract the two like fractions:
630/1680 - 1008/1680 = 630 - 1008/1680 = -378/1680
After reducing the fraction, the answer is -9/40

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