Add 21/4 and 84/81
1st number: 5 1/4, 2nd number: 1 3/81
21/4 + 84/81 is 679/108.
Steps for adding fractions
- 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,
84/81 = 84 × 4/81 × 4 = 336/324 - Add the two like fractions:
1701/324 + 336/324 = 1701 + 336/324 = 2037/324 - 2037/324 simplified gives 679/108
- So, 21/4 + 84/81 = 679/108
In mixed form: 631/108
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