Subtract 8/18 from 21/63
21/63 - 8/18 is -1/9.
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,
21/63 = 21 × 2/63 × 2 = 42/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
8/18 = 8 × 7/18 × 7 = 56/126 - Subtract the two like fractions:
42/126 - 56/126 = 42 - 56/126 = -14/126 - After reducing the fraction, the answer is -1/9
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