Subtract 4/20 from 16/81
16/81 - 4/20 is -1/405.
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,
16/81 = 16 × 20/81 × 20 = 320/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
4/20 = 4 × 81/20 × 81 = 324/1620 - Subtract the two like fractions:
320/1620 - 324/1620 = 320 - 324/1620 = -4/1620 - After reducing the fraction, the answer is -1/405
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