Add 15/18 and 21/27
15/18 + 21/27 is 29/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 27 is 54
Next, find the equivalent fraction of both fractional numbers with denominator 54 - For the 1st fraction, since 18 × 3 = 54,
15/18 = 15 × 3/18 × 3 = 45/54 - Likewise, for the 2nd fraction, since 27 × 2 = 54,
21/27 = 21 × 2/27 × 2 = 42/54 - Add the two like fractions:
45/54 + 42/54 = 45 + 42/54 = 87/54 - 87/54 simplified gives 29/18
- So, 15/18 + 21/27 = 29/18
In mixed form: 111/18
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