Add 28/90 and 56/81
28/90 + 56/81 is 406/405.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 90 × 9 = 810,
28/90 = 28 × 9/90 × 9 = 252/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
56/81 = 56 × 10/81 × 10 = 560/810 - Add the two like fractions:
252/810 + 560/810 = 252 + 560/810 = 812/810 - 812/810 simplified gives 406/405
- So, 28/90 + 56/81 = 406/405
In mixed form: 11/405
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