Add 90/81 and 28/20
1st number: 1 9/81, 2nd number: 1 8/20
90/81 + 28/20 is 113/45.
Steps for adding 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,
90/81 = 90 × 20/81 × 20 = 1800/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
28/20 = 28 × 81/20 × 81 = 2268/1620 - Add the two like fractions:
1800/1620 + 2268/1620 = 1800 + 2268/1620 = 4068/1620 - 4068/1620 simplified gives 113/45
- So, 90/81 + 28/20 = 113/45
In mixed form: 223/45
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