Question

javier writes the equation $( \frac{2}{3} )a = 50$what error did he make?

Answer 1

The given statement is "the sum of 10 and two-thirds of that tree's age, in years, is equal to 50".

If a represents a tree's age, the expression that represents this situation is

$10+\frac{2}{3}a=50$

Observe that the variable a has to multiply the fraction only.

Hence, the second option is correct: the variable a should be multiplied by 2/3 only and then added to 10.