Subtract 18/21 from 81/80
1st number: 1 1/80, 2nd number: 18/21
81/80 - 18/21 is 87/560.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
81/80 = 81 × 21/80 × 21 = 1701/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
18/21 = 18 × 80/21 × 80 = 1440/1680 - Subtract the two like fractions:
1701/1680 - 1440/1680 = 1701 - 1440/1680 = 261/1680 - After reducing the fraction, the answer is 87/560
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