Subtract 40/21 from 90/63
1st number: 1 27/63, 2nd number: 1 19/21
90/63 - 40/21 is -10/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 63 × 1 = 63,
90/63 = 90 × 1/63 × 1 = 90/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
40/21 = 40 × 3/21 × 3 = 120/63 - Subtract the two like fractions:
90/63 - 120/63 = 90 - 120/63 = -30/63 - After reducing the fraction, the answer is -10/21
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