y is inversely proportional to d^2 and when d = 10, y = 4. d is directly proportional to x^2 and when x = 2, d = 24. Find a formula for y in terms of x. Give your answer in its simplest form.

Firstly, find proportionality equation between the two variables. This should be shown as d = kx^2 and y = b/d^2.Solve to find constants of proportionality of a=6 and b=400. Eliminating for d, find that y=100/9x^4

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