The initial velocity v _ i required to project a body vertically...

The initial velocity ${v}_{i}$ required to project a body vertically upward from the surface of the earth to reach a height of $10R$, where $R$ is the radius of the earth, may be described in terms of escape velocity ${v}_{e}$ such that ${v}_{i} = \sqrt{\dfrac{x}{y}} \times {v}_{e}$. The value of $x$ will be