Add 21/81 and 28/10
1st number: 21/81, 2nd number: 2 8/10
21/81 + 28/10 is 413/135.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 10 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
21/81 = 21 × 10/81 × 10 = 210/810 - Likewise, for the 2nd fraction, since 10 × 81 = 810,
28/10 = 28 × 81/10 × 81 = 2268/810 - Add the two like fractions:
210/810 + 2268/810 = 210 + 2268/810 = 2478/810 - 2478/810 simplified gives 413/135
- So, 21/81 + 28/10 = 413/135
In mixed form: 38/135
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