Add 20/5 and 21/81
1st number: 4 0/5, 2nd number: 21/81
20/5 + 21/81 is 115/27.
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,
20/5 = 20 × 81/5 × 81 = 1620/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
21/81 = 21 × 5/81 × 5 = 105/405 - Add the two like fractions:
1620/405 + 105/405 = 1620 + 105/405 = 1725/405 - 1725/405 simplified gives 115/27
- So, 20/5 + 21/81 = 115/27
In mixed form: 47/27
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