Subtract 20/30 from 18/63
18/63 - 20/30 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 30 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 63 × 10 = 630,
18/63 = 18 × 10/63 × 10 = 180/630 - Likewise, for the 2nd fraction, since 30 × 21 = 630,
20/30 = 20 × 21/30 × 21 = 420/630 - Subtract the two like fractions:
180/630 - 420/630 = 180 - 420/630 = -240/630 - After reducing the fraction, the answer is -8/21
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