Subtract 98/81 from 18/21
1st number: 18/21, 2nd number: 1 17/81
18/21 - 98/81 is -200/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
18/21 = 18 × 27/21 × 27 = 486/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
98/81 = 98 × 7/81 × 7 = 686/567 - Subtract the two like fractions:
486/567 - 686/567 = 486 - 686/567 = -200/567
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