Subtract 90/63 from 21/30
1st number: 21/30, 2nd number: 1 27/63
21/30 - 90/63 is -51/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 63 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 30 × 21 = 630,
21/30 = 21 × 21/30 × 21 = 441/630 - Likewise, for the 2nd fraction, since 63 × 10 = 630,
90/63 = 90 × 10/63 × 10 = 900/630 - Subtract the two like fractions:
441/630 - 900/630 = 441 - 900/630 = -459/630 - After reducing the fraction, the answer is -51/70
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