Subtract 4/81 from 21/5
1st number: 4 1/5, 2nd number: 4/81
21/5 - 4/81 is 1681/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 5 × 81 = 405,
21/5 = 21 × 81/5 × 81 = 1701/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
4/81 = 4 × 5/81 × 5 = 20/405 - Subtract the two like fractions:
1701/405 - 20/405 = 1701 - 20/405 = 1681/405 - In mixed form: 461/405
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