Subtract 90/80 from 21/20
1st number: 1 1/20, 2nd number: 1 10/80
21/20 - 90/80 is -3/40.
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,
21/20 = 21 × 4/20 × 4 = 84/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
90/80 = 90 × 1/80 × 1 = 90/80 - Subtract the two like fractions:
84/80 - 90/80 = 84 - 90/80 = -6/80 - After reducing the fraction, the answer is -3/40
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