Add 80/81 and 21/4
1st number: 80/81, 2nd number: 5 1/4
80/81 + 21/4 is 2021/324.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 4 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 81 × 4 = 324,
80/81 = 80 × 4/81 × 4 = 320/324 - Likewise, for the 2nd fraction, since 4 × 81 = 324,
21/4 = 21 × 81/4 × 81 = 1701/324 - Add the two like fractions:
320/324 + 1701/324 = 320 + 1701/324 = 2021/324 - So, 80/81 + 21/4 = 2021/324
In mixed form: 677/324
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