Question

If y varies directly as x, and y is 6 when x is 72, what is the value of y when x is 8?

Answer 1

x÷y=72÷6=12    8÷12=2/3 y would equal 2/3

Answer 2

The correct answer is: y =
`(2)/(3)`

Step-by-step explanation:

The direct relation can be written as follows:

`y \propto x`

Now to remove the proportional sign, we use the constant of proportionality, let's say k, as follows:

`y = kx`

When y = 6, x = 72, k will be:

`k =(y)/(x) \\ k =(6)/(72) = (1)/(12)`

Now we know the value of k, let's find the value of y when x = 8:

`y = kx \\ y =(1)/(12) * 8 =(2)/(3)`

Hence the correct answer is: y =
`(2)/(3)`