Subtract 72/81 from 2/20
2/20 - 72/81 is -71/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 20 × 81 = 1620,
2/20 = 2 × 81/20 × 81 = 162/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
72/81 = 72 × 20/81 × 20 = 1440/1620 - Subtract the two like fractions:
162/1620 - 1440/1620 = 162 - 1440/1620 = -1278/1620 - After reducing the fraction, the answer is -71/90
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