Subtract 5/81 from 28/20
1st number: 1 8/20, 2nd number: 5/81
28/20 - 5/81 is 542/405.
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,
28/20 = 28 × 81/20 × 81 = 2268/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
5/81 = 5 × 20/81 × 20 = 100/1620 - Subtract the two like fractions:
2268/1620 - 100/1620 = 2268 - 100/1620 = 2168/1620 - After reducing the fraction, the answer is 542/405
- In mixed form: 1137/405
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