Subtract 90/81 from 20/45
1st number: 20/45, 2nd number: 1 9/81
20/45 - 90/81 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 45 × 9 = 405,
20/45 = 20 × 9/45 × 9 = 180/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
90/81 = 90 × 5/81 × 5 = 450/405 - Subtract the two like fractions:
180/405 - 450/405 = 180 - 450/405 = -270/405 - After reducing the fraction, the answer is -2/3
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