Subtract 3/81 from 21/15
1st number: 1 6/15, 2nd number: 3/81
21/15 - 3/81 is 184/135.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 15 × 27 = 405,
21/15 = 21 × 27/15 × 27 = 567/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
3/81 = 3 × 5/81 × 5 = 15/405 - Subtract the two like fractions:
567/405 - 15/405 = 567 - 15/405 = 552/405 - After reducing the fraction, the answer is 184/135
- In mixed form: 149/135
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