Add 80/81 and 3/5
80/81 + 3/5 is 643/405.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 5 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
80/81 = 80 × 5/81 × 5 = 400/405 - Likewise, for the 2nd fraction, since 5 × 81 = 405,
3/5 = 3 × 81/5 × 81 = 243/405 - Add the two like fractions:
400/405 + 243/405 = 400 + 243/405 = 643/405 - So, 80/81 + 3/5 = 643/405
In mixed form: 1238/405
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