Add 21/45 and 30/81
21/45 + 30/81 is 113/135.
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,
21/45 = 21 × 9/45 × 9 = 189/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
30/81 = 30 × 5/81 × 5 = 150/405 - Add the two like fractions:
189/405 + 150/405 = 189 + 150/405 = 339/405 - 339/405 simplified gives 113/135
- So, 21/45 + 30/81 = 113/135
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