Subtract 5/81 from 42/15
1st number: 2 12/15, 2nd number: 5/81
42/15 - 5/81 is 1109/405.
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,
42/15 = 42 × 27/15 × 27 = 1134/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
5/81 = 5 × 5/81 × 5 = 25/405 - Subtract the two like fractions:
1134/405 - 25/405 = 1134 - 25/405 = 1109/405 - In mixed form: 2299/405
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