Add 28/30 and 20/81
28/30 + 20/81 is 478/405.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 30 × 27 = 810,
28/30 = 28 × 27/30 × 27 = 756/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
20/81 = 20 × 10/81 × 10 = 200/810 - Add the two like fractions:
756/810 + 200/810 = 756 + 200/810 = 956/810 - 956/810 simplified gives 478/405
- So, 28/30 + 20/81 = 478/405
In mixed form: 173/405
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