Subtract 21/18 from 20/63
1st number: 20/63, 2nd number: 1 3/18
20/63 - 21/18 is -107/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 63 × 2 = 126,
20/63 = 20 × 2/63 × 2 = 40/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Subtract the two like fractions:
40/126 - 147/126 = 40 - 147/126 = -107/126
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