Subtract 90/63 from 20/36, Solve 20/36

Subtract 90/63 from 20/36

1^st number: 20/36, 2^nd number: 1 27/63

20/36 - 90/63 is -55/63.

Find the least common denominator or LCM of the two denominators:
LCM of 36 and 63 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 36 × 7 = 252,
20/36 = 20 × 7/36 × 7 = 140/252
Likewise, for the 2nd fraction, since 63 × 4 = 252,
90/63 = 90 × 4/63 × 4 = 360/252
Subtract the two like fractions:
140/252 - 360/252 = 140 - 360/252 = -220/252
After reducing the fraction, the answer is -55/63

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