Subtract 90/81 from 30/63
1st number: 30/63, 2nd number: 1 9/81
30/63 - 90/81 is -40/63.
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,
30/63 = 30 × 9/63 × 9 = 270/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
90/81 = 90 × 7/81 × 7 = 630/567 - Subtract the two like fractions:
270/567 - 630/567 = 270 - 630/567 = -360/567 - After reducing the fraction, the answer is -40/63
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