Subtract 1/81 from 21/15
1st number: 1 6/15, 2nd number: 1/81
21/15 - 1/81 is 562/405.
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,
1/81 = 1 × 5/81 × 5 = 5/405 - Subtract the two like fractions:
567/405 - 5/405 = 567 - 5/405 = 562/405 - In mixed form: 1157/405
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