Subtract 90/63 from 42/81
1st number: 42/81, 2nd number: 1 27/63
42/81 - 90/63 is -172/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 63 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
42/81 = 42 × 7/81 × 7 = 294/567 - Likewise, for the 2nd fraction, since 63 × 9 = 567,
90/63 = 90 × 9/63 × 9 = 810/567 - Subtract the two like fractions:
294/567 - 810/567 = 294 - 810/567 = -516/567 - After reducing the fraction, the answer is -172/189
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Related: 84/81-90/63