Add 42/81 and 8/20
42/81 + 8/20 is 124/135.
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,
42/81 = 42 × 20/81 × 20 = 840/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
8/20 = 8 × 81/20 × 81 = 648/1620 - Add the two like fractions:
840/1620 + 648/1620 = 840 + 648/1620 = 1488/1620 - 1488/1620 simplified gives 124/135
- So, 42/81 + 8/20 = 124/135
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