y is inversely proportional to x and y = 4 when x = ...
y is inversely proportional to x and y = 4 when x = 1/2. Find x when y = 10.
2.5
10
1/5
1/10
Correct answer is C
y ∝ 1/x
y = K/x
K = xy
K = (1/2) * 4 ( when y = 4 and x = 1/2)
K = 2
∴y = 2/x
10 = 2/x (when y = 10)
10x = 2
x = 2/10
x = 1/5