Subtract 21/5 from 7/81
1st number: 7/81, 2nd number: 4 1/5
7/81 - 21/5 is -1666/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 5 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
7/81 = 7 × 5/81 × 5 = 35/405 - Likewise, for the 2nd fraction, since 5 × 81 = 405,
21/5 = 21 × 81/5 × 81 = 1701/405 - Subtract the two like fractions:
35/405 - 1701/405 = 35 - 1701/405 = -1666/405
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