Subtract 81/80 from 10/20
1st number: 10/20, 2nd number: 1 1/80
10/20 - 81/80 is -41/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 20 × 4 = 80,
10/20 = 10 × 4/20 × 4 = 40/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
81/80 = 81 × 1/80 × 1 = 81/80 - Subtract the two like fractions:
40/80 - 81/80 = 40 - 81/80 = -41/80
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