Subtract 81/42 from 18/80
1st number: 18/80, 2nd number: 1 39/42
18/80 - 81/42 is -477/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 42 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
18/80 = 18 × 21/80 × 21 = 378/1680 - Likewise, for the 2nd fraction, since 42 × 40 = 1680,
81/42 = 81 × 40/42 × 40 = 3240/1680 - Subtract the two like fractions:
378/1680 - 3240/1680 = 378 - 3240/1680 = -2862/1680 - After reducing the fraction, the answer is -477/280
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