Subtract 4/20 from 1/81
1/81 - 4/20 is -76/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 20 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 81 × 20 = 1620,
1/81 = 1 × 20/81 × 20 = 20/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
4/20 = 4 × 81/20 × 81 = 324/1620 - Subtract the two like fractions:
20/1620 - 324/1620 = 20 - 324/1620 = -304/1620 - After reducing the fraction, the answer is -76/405
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