Question

A student is running a 5-kilometer race. He runs 1 kilometer every 3 minutes. Select the function that describes his distance from the finish line after x minutes.

f(x) = − 1 over 3 x + 5
f(x) = − 1 over 5 x + 3
f(x) = 1 over 5 x + 5
f(x) = 1 over 3 x + 3

Answer 1

-1/5x+3 because u have ran -1 out of 5 kilometers

Answer 2

Answer: The correct option is

(D)
`f(x)=(1)/(3)x+5.`

Step-by-step explanation: Given that a student is running a 5-kilometer race. He runs 1 kilometer every 3 minutes.

We are to select the function that describes his distance from the finish line after x minutes.

When the student reaches the finish line, he already covered a distance of 5 kilometers.

Now, in 3 minutes, distance covered by the student = 1 kilometer.

So, in 1 minute, distance covered by the student is given by

`(1)/(3)~\textup{kilometer}.`

Therefore, in x minutes, the distance covered by the student is

`(1)/(3)x~\textup{kilometer}.`

That is, the total distance from the finish line after x minutes is given by

`f(x)=(1)/(3)x+5.`

Thus, option (D) is CORRECT.