Add 7/20 and 4/81
7/20 + 4/81 is 647/1620.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 20 × 81 = 1620,
7/20 = 7 × 81/20 × 81 = 567/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
4/81 = 4 × 20/81 × 20 = 80/1620 - Add the two like fractions:
567/1620 + 80/1620 = 567 + 80/1620 = 647/1620 - So, 7/20 + 4/81 = 647/1620
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