An object of mass $m$ is thrown vertically upward from the surface of Mars, where the acceleration due to gravity is $g_b$. The object's initial speed is $v_b$, and it reaches a maximum height of $y_b$.
A similar object is thrown upward with initial speed $v_a = 4v_b$ from the surface of Saturn's moon Titan. Its maximum height is $y_a$. The acceleration due to gravity on Titan is $g_a$.