Add 42/15 and 21/81
1st number: 2 12/15, 2nd number: 21/81
42/15 + 21/81 is 413/135.
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,
42/15 = 42 × 27/15 × 27 = 1134/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
21/81 = 21 × 5/81 × 5 = 105/405 - Add the two like fractions:
1134/405 + 105/405 = 1134 + 105/405 = 1239/405 - 1239/405 simplified gives 413/135
- So, 42/15 + 21/81 = 413/135
In mixed form: 38/135
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