Subtract 20/18 from 54/70, Solve 54/70

Subtract 20/18 from 54/70

1^st number: 54/70, 2^nd number: 1 2/18

54/70 - 20/18 is -107/315.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 18 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
54/70 = 54 × 9/70 × 9 = 486/630
Likewise, for the 2nd fraction, since 18 × 35 = 630,
20/18 = 20 × 35/18 × 35 = 700/630
Subtract the two like fractions:
486/630 - 700/630 = 486 - 700/630 = -214/630
After reducing the fraction, the answer is -107/315

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