Subtract 21/81 from 45/9
1st number: 5 0/9, 2nd number: 21/81
45/9 - 21/81 is 128/27.
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,
45/9 = 45 × 9/9 × 9 = 405/81 - Likewise, for the 2nd fraction, since 81 × 1 = 81,
21/81 = 21 × 1/81 × 1 = 21/81 - Subtract the two like fractions:
405/81 - 21/81 = 405 - 21/81 = 384/81 - After reducing the fraction, the answer is 128/27
- In mixed form: 420/27
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