Subtract 18/8 from 63/70, Solve 63/70

Subtract 18/8 from 63/70

1^st number: 63/70, 2^nd number: 2 2/8

63/70 - 18/8 is -27/20.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 8 is 280

Next, find the equivalent fraction of both fractional numbers with denominator 280
For the 1st fraction, since 70 × 4 = 280,
63/70 = 63 × 4/70 × 4 = 252/280
Likewise, for the 2nd fraction, since 8 × 35 = 280,
18/8 = 18 × 35/8 × 35 = 630/280
Subtract the two like fractions:
252/280 - 630/280 = 252 - 630/280 = -378/280
After reducing the fraction, the answer is -27/20

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