Add 21/27 and 20/30
21/27 + 20/30 is 13/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 30 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 27 × 10 = 270,
21/27 = 21 × 10/27 × 10 = 210/270 - Likewise, for the 2nd fraction, since 30 × 9 = 270,
20/30 = 20 × 9/30 × 9 = 180/270 - Add the two like fractions:
210/270 + 180/270 = 210 + 180/270 = 390/270 - 390/270 simplified gives 13/9
- So, 21/27 + 20/30 = 13/9
In mixed form: 14/9
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