Add 42/45 and 21/81
42/45 + 21/81 is 161/135.
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,
21/81 = 21 × 5/81 × 5 = 105/405 - Add the two like fractions:
378/405 + 105/405 = 378 + 105/405 = 483/405 - 483/405 simplified gives 161/135
- So, 42/45 + 21/81 = 161/135
In mixed form: 126/135
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