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