Subtract 90/63 from 20/18, Solve 1 2/18

Subtract 90/63 from 20/18

1^st number: 1 2/18, 2^nd number: 1 27/63

20/18 - 90/63 is -20/63.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 63 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
20/18 = 20 × 7/18 × 7 = 140/126
Likewise, for the 2nd fraction, since 63 × 2 = 126,
90/63 = 90 × 2/63 × 2 = 180/126
Subtract the two like fractions:
140/126 - 180/126 = 140 - 180/126 = -40/126
After reducing the fraction, the answer is -20/63

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