Add 4/5 and 21/81
4/5 + 21/81 is 143/135.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 5 × 81 = 405,
4/5 = 4 × 81/5 × 81 = 324/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
21/81 = 21 × 5/81 × 5 = 105/405 - Add the two like fractions:
324/405 + 105/405 = 324 + 105/405 = 429/405 - 429/405 simplified gives 143/135
- So, 4/5 + 21/81 = 143/135
In mixed form: 18/135
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