Subtract 35/20 from 72/81
1st number: 72/81, 2nd number: 1 15/20
72/81 - 35/20 is -31/36.
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,
72/81 = 72 × 20/81 × 20 = 1440/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
35/20 = 35 × 81/20 × 81 = 2835/1620 - Subtract the two like fractions:
1440/1620 - 2835/1620 = 1440 - 2835/1620 = -1395/1620 - After reducing the fraction, the answer is -31/36
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