Add 21/30 and 42/81
21/30 + 42/81 is 329/270.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 30 × 27 = 810,
21/30 = 21 × 27/30 × 27 = 567/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
42/81 = 42 × 10/81 × 10 = 420/810 - Add the two like fractions:
567/810 + 420/810 = 567 + 420/810 = 987/810 - 987/810 simplified gives 329/270
- So, 21/30 + 42/81 = 329/270
In mixed form: 159/270
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