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A variable y is inversely proportional to x2, when y = 10, x = 2….

A variable y is inversely proportional to x², when y = 10, x = 2. What is y when x = 10?

A.
2
B.
4
C.
100
D.
0.4
E.
0.1

Correct Answer: Option D

Explanation

y (alpha) (frac{1}{x^2})
y = (frac{k}{x^2})
k = x²y
= (2)² x 10
= 40
y = (frac{40}{x^2})
= (frac{40}{(10)^2})
= (frac{40}{100})
= 0.4