Add 21/27 and 28/30
21/27 + 28/30 is 77/45.
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,
28/30 = 28 × 9/30 × 9 = 252/270 - Add the two like fractions:
210/270 + 252/270 = 210 + 252/270 = 462/270 - 462/270 simplified gives 77/45
- So, 21/27 + 28/30 = 77/45
In mixed form: 132/45
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