Question

MATH HELP PLEEEEEASE

The function f(x) varies inversely with x and f(x)=2 when x=16.
What is f(x) when x=4?

♦ 128
♦ 72
♦ 40
♦ 8

Answer 1

varying inversely means f(x)=a constant divided by x, f(x)=k/x
find k: f(16)=k/16=2, k=32
so the function is f(x)=32/x
when x=4: f(4)=32/4=8
the answer is D.