Subtract 80/21 from 90/27
1st number: 3 9/27, 2nd number: 3 17/21
90/27 - 80/21 is -10/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 21 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 27 × 7 = 189,
90/27 = 90 × 7/27 × 7 = 630/189 - Likewise, for the 2nd fraction, since 21 × 9 = 189,
80/21 = 80 × 9/21 × 9 = 720/189 - Subtract the two like fractions:
630/189 - 720/189 = 630 - 720/189 = -90/189 - After reducing the fraction, the answer is -10/21
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