Add 21/4 and 3/81, Solve 5 1/4 + 3/81 as a fraction

Add 21/4 and 3/81

1^st number: 5 1/4, 2^nd number: 3/81

21/4 + 3/81 is 571/108.

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,
21/4 = 21 × 81/4 × 81 = 1701/324
Likewise, for the 2nd fraction, since 81 × 4 = 324,
3/81 = 3 × 4/81 × 4 = 12/324
Add the two like fractions:
1701/324 + 12/324 = 1701 + 12/324 = 1713/324
1713/324 simplified gives 571/108
So, 21/4 + 3/81 = 571/108
In mixed form: 531/108

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