Add 28/30 and 21/81
28/30 + 21/81 is 161/135.
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,
21/81 = 21 × 10/81 × 10 = 210/810 - Add the two like fractions:
756/810 + 210/810 = 756 + 210/810 = 966/810 - 966/810 simplified gives 161/135
- So, 28/30 + 21/81 = 161/135
In mixed form: 126/135
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