Subtract 9/10 from 21/63
21/63 - 9/10 is -17/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 10 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 10 × 63 = 630,
9/10 = 9 × 63/10 × 63 = 567/630 - Subtract the two like fractions:
210/630 - 567/630 = 210 - 567/630 = -357/630 - After reducing the fraction, the answer is -17/30
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