Subtract 90/81 from 12/21
1st number: 12/21, 2nd number: 1 9/81
12/21 - 90/81 is -34/63.
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,
12/21 = 12 × 27/21 × 27 = 324/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
90/81 = 90 × 7/81 × 7 = 630/567 - Subtract the two like fractions:
324/567 - 630/567 = 324 - 630/567 = -306/567 - After reducing the fraction, the answer is -34/63
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