Add 12/15 and 42/81
12/15 + 42/81 is 178/135.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 15 × 27 = 405,
12/15 = 12 × 27/15 × 27 = 324/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
42/81 = 42 × 5/81 × 5 = 210/405 - Add the two like fractions:
324/405 + 210/405 = 324 + 210/405 = 534/405 - 534/405 simplified gives 178/135
- So, 12/15 + 42/81 = 178/135
In mixed form: 143/135
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