Add 21/12 and 81/20
1st number: 1 9/12, 2nd number: 4 1/20
21/12 + 81/20 is 29/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
21/12 = 21 × 5/12 × 5 = 105/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
81/20 = 81 × 3/20 × 3 = 243/60 - Add the two like fractions:
105/60 + 243/60 = 105 + 243/60 = 348/60 - 348/60 simplified gives 29/5
- So, 21/12 + 81/20 = 29/5
In mixed form: 54/5
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