Add 15/21 and 20/81
15/21 + 20/81 is 545/567.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
15/21 = 15 × 27/21 × 27 = 405/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
20/81 = 20 × 7/81 × 7 = 140/567 - Add the two like fractions:
405/567 + 140/567 = 405 + 140/567 = 545/567 - So, 15/21 + 20/81 = 545/567
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