Add 15/18 and 21/54
15/18 + 21/54 is 11/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 54 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 54 × 1 = 54,
21/54 = 21 × 1/54 × 1 = 21/54 - Add the two like fractions:
45/54 + 21/54 = 45 + 21/54 = 66/54 - 66/54 simplified gives 11/9
- So, 15/18 + 21/54 = 11/9
In mixed form: 12/9
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