Answer:
[tex]\frac{(x + 4)^{2}}{3x}[/tex]
Step-by-step explanation:
Let the number that Lena thinks of is x.
Then she finds the sum of the number and 4 i.e. (x + 4).
Then she squared the entire quantity as (x + 4)².
Now, she divided the final term by the product of 3 and the number.
Here, the product of 3 and the number is 3x.
Therefore, ultimately Lena will get the algebraic expression as [tex]\frac{(x + 4)^{2}}{3x}[/tex]. (Answer)