Add 18/9 and 21/12
1st number: 2 0/9, 2nd number: 1 9/12
18/9 + 21/12 is 15/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 12 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 9 × 4 = 36,
18/9 = 18 × 4/9 × 4 = 72/36 - Likewise, for the 2nd fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36 - Add the two like fractions:
72/36 + 63/36 = 72 + 63/36 = 135/36 - 135/36 simplified gives 15/4
- So, 18/9 + 21/12 = 15/4
In mixed form: 33/4
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