Add 21/81 and 12/20
21/81 + 12/20 is 116/135.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 20 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 81 × 20 = 1620,
21/81 = 21 × 20/81 × 20 = 420/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
12/20 = 12 × 81/20 × 81 = 972/1620 - Add the two like fractions:
420/1620 + 972/1620 = 420 + 972/1620 = 1392/1620 - 1392/1620 simplified gives 116/135
- So, 21/81 + 12/20 = 116/135
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