Subtract 28/20 from 28/81
1st number: 28/81, 2nd number: 1 8/20
28/81 - 28/20 is -427/405.
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,
28/81 = 28 × 20/81 × 20 = 560/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
28/20 = 28 × 81/20 × 81 = 2268/1620 - Subtract the two like fractions:
560/1620 - 2268/1620 = 560 - 2268/1620 = -1708/1620 - After reducing the fraction, the answer is -427/405
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