Add 25/4 and 21/81, Solve 6 1/4 + 21/81 as a fraction

Add 25/4 and 21/81

1^st number: 6 1/4, 2^nd number: 21/81

25/4 + 21/81 is 703/108.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 81 is 324

Next, find the equivalent fraction of both fractional numbers with denominator 324
For the 1st fraction, since 4 × 81 = 324,
25/4 = 25 × 81/4 × 81 = 2025/324
Likewise, for the 2nd fraction, since 81 × 4 = 324,
21/81 = 21 × 4/81 × 4 = 84/324
Add the two like fractions:
2025/324 + 84/324 = 2025 + 84/324 = 2109/324
2109/324 simplified gives 703/108
So, 25/4 + 21/81 = 703/108
In mixed form: 655/108

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