Add 21/12 and 40/81
1st number: 1 9/12, 2nd number: 40/81
21/12 + 40/81 is 727/324.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 12 × 27 = 324,
21/12 = 21 × 27/12 × 27 = 567/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
40/81 = 40 × 4/81 × 4 = 160/324 - Add the two like fractions:
567/324 + 160/324 = 567 + 160/324 = 727/324 - So, 21/12 + 40/81 = 727/324
In mixed form: 279/324
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