Answer:
is the CORRECT equation.
Step-by-step explanation:
The given question is INCOMPLETE.
Javier asks his mother how old a tree in their yard is. His mother says, “The sum of 10 and two-thirds of that tree’s age, in years, is equal to 50.” Javier writes the equation { 10 + 2/3} where a is the tree’s age in years. His equation is not correct. What error did he make?
Now here:
a: The tree’s age in years.
Also, “The sum of 10 and two-thirds of that tree’s age, in years, is equal to 50.”
⇒ 10 + two-thirds of that tree’s age = 50

But in the equation written by Javier, the the third fraction is NOT MULTIPLIED by the age of the tree a in Years.
So, the written equation by Javier is Incorrect.
Now, solving the written correct equation for the value of a, we get:

Hence the correct age of the tree = 60 years