Add 21/30 and 45/54
21/30 + 45/54 is 23/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 30 × 9 = 270,
21/30 = 21 × 9/30 × 9 = 189/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
45/54 = 45 × 5/54 × 5 = 225/270 - Add the two like fractions:
189/270 + 225/270 = 189 + 225/270 = 414/270 - 414/270 simplified gives 23/15
- So, 21/30 + 45/54 = 23/15
In mixed form: 18/15
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