Subtract 1/4 from 20/81
20/81 - 1/4 is -1/324.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 4 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 81 × 4 = 324,
20/81 = 20 × 4/81 × 4 = 80/324 - Likewise, for the 2nd fraction, since 4 × 81 = 324,
1/4 = 1 × 81/4 × 81 = 81/324 - Subtract the two like fractions:
80/324 - 81/324 = 80 - 81/324 = -1/324
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