Solving a Ratio Problem with Three Variables

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A question that just popped in my head after reading an article:

If the radius of Planet X is 16% larger than that of Earth, and Planet X has 40% the radius of Planet Y, then what is the radius of Planet Y in terms of Earth radii?

I'm having trouble trying to figure this one out. How would we solve this one?

I understand we may have to define one variable in terms of another to get the desired result, but again, I seem to be failing miserably at it.

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Let $X$, $Y$ and $E$ be the radii of the two planets and Earth, respectively. Then

$X = 1.16E$

and

$X = 1.40Y$

Substitution gives you $1.16E = 1.40Y$

Solve that equation for $Y$ and you'll have the result that you're looking for.