Subtract 81/80 from 2/21
1st number: 2/21, 2nd number: 1 1/80
2/21 - 81/80 is -1541/1680.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
2/21 = 2 × 80/21 × 80 = 160/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
81/80 = 81 × 21/80 × 21 = 1701/1680 - Subtract the two like fractions:
160/1680 - 1701/1680 = 160 - 1701/1680 = -1541/1680
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