Add 42/45 and 20/81
42/45 + 20/81 is 478/405.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 45 × 9 = 405,
42/45 = 42 × 9/45 × 9 = 378/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
20/81 = 20 × 5/81 × 5 = 100/405 - Add the two like fractions:
378/405 + 100/405 = 378 + 100/405 = 478/405 - So, 42/45 + 20/81 = 478/405
In mixed form: 173/405
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