Add 15/30 and 21/27
15/30 + 21/27 is 23/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 27 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 30 × 9 = 270,
15/30 = 15 × 9/30 × 9 = 135/270 - Likewise, for the 2nd fraction, since 27 × 10 = 270,
21/27 = 21 × 10/27 × 10 = 210/270 - Add the two like fractions:
135/270 + 210/270 = 135 + 210/270 = 345/270 - 345/270 simplified gives 23/18
- So, 15/30 + 21/27 = 23/18
In mixed form: 15/18
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