Add 42/81 and 15/20
42/81 + 15/20 is 137/108.
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,
42/81 = 42 × 20/81 × 20 = 840/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
15/20 = 15 × 81/20 × 81 = 1215/1620 - Add the two like fractions:
840/1620 + 1215/1620 = 840 + 1215/1620 = 2055/1620 - 2055/1620 simplified gives 137/108
- So, 42/81 + 15/20 = 137/108
In mixed form: 129/108
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