Subtract 20/63 from 21/70
21/70 - 20/63 is -11/630.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 63 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Likewise, for the 2nd fraction, since 63 × 10 = 630,
20/63 = 20 × 10/63 × 10 = 200/630 - Subtract the two like fractions:
189/630 - 200/630 = 189 - 200/630 = -11/630
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