Subtract 18/30 from 21/63
21/63 - 18/30 is -4/15.
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,
21/63 = 21 × 10/63 × 10 = 210/630 - Likewise, for the 2nd fraction, since 30 × 21 = 630,
18/30 = 18 × 21/30 × 21 = 378/630 - Subtract the two like fractions:
210/630 - 378/630 = 210 - 378/630 = -168/630 - After reducing the fraction, the answer is -4/15
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