Add 25/8 and 21/81, Solve 3 1/8 + 21/81 as a fraction

Add 25/8 and 21/81

1^st number: 3 1/8, 2^nd number: 21/81

25/8 + 21/81 is 731/216.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 81 is 648

Next, find the equivalent fraction of both fractional numbers with denominator 648
For the 1st fraction, since 8 × 81 = 648,
25/8 = 25 × 81/8 × 81 = 2025/648
Likewise, for the 2nd fraction, since 81 × 8 = 648,
21/81 = 21 × 8/81 × 8 = 168/648
Add the two like fractions:
2025/648 + 168/648 = 2025 + 168/648 = 2193/648
2193/648 simplified gives 731/216
So, 25/8 + 21/81 = 731/216
In mixed form: 383/216

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