Add 21/12 and 9/5
1st number: 1 9/12, 2nd number: 1 4/5
21/12 + 9/5 is 71/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 5 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 5 × 12 = 60,
9/5 = 9 × 12/5 × 12 = 108/60 - Add the two like fractions:
105/60 + 108/60 = 105 + 108/60 = 213/60 - 213/60 simplified gives 71/20
- So, 21/12 + 9/5 = 71/20
In mixed form: 311/20
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