Add 54/81 and 21/5
1st number: 54/81, 2nd number: 4 1/5
54/81 + 21/5 is 73/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 5 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
54/81 = 54 × 5/81 × 5 = 270/405 - Likewise, for the 2nd fraction, since 5 × 81 = 405,
21/5 = 21 × 81/5 × 81 = 1701/405 - Add the two like fractions:
270/405 + 1701/405 = 270 + 1701/405 = 1971/405 - 1971/405 simplified gives 73/15
- So, 54/81 + 21/5 = 73/15
In mixed form: 413/15
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