Subtract 63/70 from 30/42, Solve 30/42

Subtract 63/70 from 30/42

30/42 - 63/70 is -13/70.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
30/42 = 30 × 5/42 × 5 = 150/210
Likewise, for the 2nd fraction, since 70 × 3 = 210,
63/70 = 63 × 3/70 × 3 = 189/210
Subtract the two like fractions:
150/210 - 189/210 = 150 - 189/210 = -39/210
After reducing the fraction, the answer is -13/70

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