Subtract 20/81 from 42/9
1st number: 4 6/9, 2nd number: 20/81
42/9 - 20/81 is 358/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 81 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 9 × 9 = 81,
42/9 = 42 × 9/9 × 9 = 378/81 - Likewise, for the 2nd fraction, since 81 × 1 = 81,
20/81 = 20 × 1/81 × 1 = 20/81 - Subtract the two like fractions:
378/81 - 20/81 = 378 - 20/81 = 358/81 - In mixed form: 434/81
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