Subtract 20/81 from 90/20
1st number: 4 10/20, 2nd number: 20/81
90/20 - 20/81 is 689/162.
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,
90/20 = 90 × 81/20 × 81 = 7290/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
20/81 = 20 × 20/81 × 20 = 400/1620 - Subtract the two like fractions:
7290/1620 - 400/1620 = 7290 - 400/1620 = 6890/1620 - After reducing the fraction, the answer is 689/162
- In mixed form: 441/162
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