Add 15/20 and 21/18
1st number: 15/20, 2nd number: 1 3/18
15/20 + 21/18 is 23/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
15/20 = 15 × 9/20 × 9 = 135/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
21/18 = 21 × 10/18 × 10 = 210/180 - Add the two like fractions:
135/180 + 210/180 = 135 + 210/180 = 345/180 - 345/180 simplified gives 23/12
- So, 15/20 + 21/18 = 23/12
In mixed form: 111/12
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