Add 21/54 and 15/30
21/54 + 15/30 is 8/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 30 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Likewise, for the 2nd fraction, since 30 × 9 = 270,
15/30 = 15 × 9/30 × 9 = 135/270 - Add the two like fractions:
105/270 + 135/270 = 105 + 135/270 = 240/270 - 240/270 simplified gives 8/9
- So, 21/54 + 15/30 = 8/9
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