
From the FBD of 40 kN block
$\Sigma F_H = 0$
$R_1 \sin 80^\circ = R_2 \sin 30^\circ$
$R_1 = \dfrac{R_2 \sin 30^\circ}{\sin 80^\circ}$
$R_1 = 0.5077R_2$
$\Sigma F_V = 0$
$R_2 \cos 30^\circ + R_1 \cos 80^\circ = 40$
$R_2 \cos 30^\circ + (0.5077R_2) \cos 80^\circ = 40$
$0.9542R_2 = 40$
$R_2 = 41.92 \, \text{ kN}$
From the FBD of lower block
$\Sigma F_V = 0$
$R_3 \cos 20^\circ = R_2 \cos 30^\circ$
$R_3 \cos 20^\circ = 41.92 \cos 30^\circ$
$R_3 = 38.634 \, \text{ kN}$
$\Sigma F_H = 0$
$P = R_2 \sin 30^\circ + R_3 \sin 20^\circ$
$P = 41.92 \sin 30^\circ + 38.634 \sin 20^\circ$
$P = 34.174 \, \text{ kN}$ answer