Add 21/18 and 12/9
1st number: 1 3/18, 2nd number: 1 3/9
21/18 + 12/9 is 5/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 9 is 18
Next, find the equivalent fraction of both fractional numbers with denominator 18 - For the 1st fraction, since 18 × 1 = 18,
21/18 = 21 × 1/18 × 1 = 21/18 - Likewise, for the 2nd fraction, since 9 × 2 = 18,
12/9 = 12 × 2/9 × 2 = 24/18 - Add the two like fractions:
21/18 + 24/18 = 21 + 24/18 = 45/18 - 45/18 simplified gives 5/2
- So, 21/18 + 12/9 = 5/2
In mixed form: 21/2
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