Add 81/84 and 90/81, Solve 81/84 + 1 9/81 as a fraction

Add 81/84 and 90/81

1^st number: 81/84, 2^nd number: 1 9/81

81/84 + 90/81 is 523/252.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 81 is 2268

Next, find the equivalent fraction of both fractional numbers with denominator 2268
For the 1st fraction, since 84 × 27 = 2268,
81/84 = 81 × 27/84 × 27 = 2187/2268
Likewise, for the 2nd fraction, since 81 × 28 = 2268,
90/81 = 90 × 28/81 × 28 = 2520/2268
Add the two like fractions:
2187/2268 + 2520/2268 = 2187 + 2520/2268 = 4707/2268
4707/2268 simplified gives 523/252
So, 81/84 + 90/81 = 523/252
In mixed form: 219/252

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