Add 21/5 and 30/81
1st number: 4 1/5, 2nd number: 30/81
21/5 + 30/81 is 617/135.
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,
21/5 = 21 × 81/5 × 81 = 1701/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
30/81 = 30 × 5/81 × 5 = 150/405 - Add the two like fractions:
1701/405 + 150/405 = 1701 + 150/405 = 1851/405 - 1851/405 simplified gives 617/135
- So, 21/5 + 30/81 = 617/135
In mixed form: 477/135
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