Add 21/81 and 4/45
21/81 + 4/45 is 47/135.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 45 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
21/81 = 21 × 5/81 × 5 = 105/405 - Likewise, for the 2nd fraction, since 45 × 9 = 405,
4/45 = 4 × 9/45 × 9 = 36/405 - Add the two like fractions:
105/405 + 36/405 = 105 + 36/405 = 141/405 - 141/405 simplified gives 47/135
- So, 21/81 + 4/45 = 47/135
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