Subtract 21/18 from 81/80
1st number: 1 1/80, 2nd number: 1 3/18
81/80 - 21/18 is -37/240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 18 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
81/80 = 81 × 9/80 × 9 = 729/720 - Likewise, for the 2nd fraction, since 18 × 40 = 720,
21/18 = 21 × 40/18 × 40 = 840/720 - Subtract the two like fractions:
729/720 - 840/720 = 729 - 840/720 = -111/720 - After reducing the fraction, the answer is -37/240
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