The function f(x) varies inversely with x and f(x) = 4 when x = 12.
2 answers:
<h3>Answer: C. 16.</h3>
Step-by-step explanation:
We are given inverse relation between f(x) and x.
The function f(x) varies inversely with x.
Inverse relation could be written as
f(x) = .
We also given f(x) = 4 when x = 12.
Plugging f(x) = 4 and x=12 in the above inverse relation to get the value of constant k.
.
On cross multiplying, we get
12× 4 =
48 = k
Now, we need to find f(x) for x=3.
Plugging k=48 and x=3 in inverse relation, we get
.
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