In the linear programming problem,

Maximize $Z = 48X_1 + 36X_2$

Subject to:

• $X_1 \leq 5$
• $X_2 \leq 8$
• $2X_1 + \frac{4}{3}X_2 \leq 16$
• $X_1 + X_2 = 10$
• $X_1 \geq 4$
• $X_1 \geq 0, X_2 \geq 0$

The value of $Z$ is ______.