Subtract 90/63 from 3/21
1st number: 3/21, 2nd number: 1 27/63
3/21 - 90/63 is -9/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
3/21 = 3 × 3/21 × 3 = 9/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
90/63 = 90 × 1/63 × 1 = 90/63 - Subtract the two like fractions:
9/63 - 90/63 = 9 - 90/63 = -81/63 - After reducing the fraction, the answer is -9/7
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