Subtract 90/81 from 28/63
1st number: 28/63, 2nd number: 1 9/81
28/63 - 90/81 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 63 × 9 = 567,
28/63 = 28 × 9/63 × 9 = 252/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
90/81 = 90 × 7/81 × 7 = 630/567 - Subtract the two like fractions:
252/567 - 630/567 = 252 - 630/567 = -378/567 - After reducing the fraction, the answer is -2/3
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