Subtract 90/81 from 9/20
1st number: 9/20, 2nd number: 1 9/81
9/20 - 90/81 is -119/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 20 × 81 = 1620,
9/20 = 9 × 81/20 × 81 = 729/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
90/81 = 90 × 20/81 × 20 = 1800/1620 - Subtract the two like fractions:
729/1620 - 1800/1620 = 729 - 1800/1620 = -1071/1620 - After reducing the fraction, the answer is -119/180
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