Question

A student is running a 3-kilometer race. He runs 1 kilometer every 2 minutes. Select the function that describes his distance from the finish line after x minutes. f(x) = − 1 over 3x + 2 f(x) = − 1 over 2x + 3 f(x) = 1 over 2x + 3 f(x) = 1 over 3x + 2

Answer 1

We have been given that the student runs 1 kilometer every 2 minutes. Therefore, the velocity of the student is given by $\frac{1}{2} \text{ km/min}$

We know the formula

$\text{Velocity}=\frac{\text{Distance}}{\text{Time}}$

Thus, the distance traveled after x minutes is given by $\frac{1}{2}x$

Therefore, the distance traveled from the finish line is given by

$f(x)=3-\frac{1}{2} x\\ \\ f(x)=-\frac{1}{2} x+3$

Therefore, second option is correct.