Solve the Fraction Equation: Finding the Missing Addend in 2/9 + ? = 2/3

To find the missing fraction in the equation $\frac{2}{9} + ? = \frac{2}{3}$, we will perform the following steps:

• Step 1: Convert the fraction $\frac{2}{3}$ to have the same denominator as $\frac{2}{9}$.
• Step 2: Subtract $\frac{2}{9}$ from the new fraction.

Let's execute these steps:
Step 1: Convert $\frac{2}{3}$ into a fraction with a denominator of 9. To do this, multiply both the numerator and the denominator of $\frac{2}{3}$ by 3 to obtain an equivalent fraction:
$\frac{2}{3} \times \frac{3}{3} = \frac{6}{9}$

Step 2: Subtract $\frac{2}{9}$ from $\frac{6}{9}$:
$\frac{6}{9} - \frac{2}{9} = \frac{4}{9}$

Thus, the fraction that we need to add to $\frac{2}{9}$ to get $\frac{2}{3}$ is $\frac{4}{9}$.

The correct answer to the problem is $\frac{4}{9}$.