Question

An animal is running at a rate of 40 ft per sec.(a) If the animal runs for 5 sec, what is its distance?(b) If the animal travels d ft, what is its time?If the animal travels d ft, it’s time is : _____(Use integers or fractions for any numbers)Is the answer in ft per sec, ft., or just sec.?

Answer 1

ANSWERS

(a) d = 200 ft

(b) t = d/40 sec

Step-by-step explanation

The animal is running at a rate of 40 feet per second. Given the units of this rate, we can conclude that this rate is the quotiend between distance (in feet) and time (in seconds),

`40(ft)/(sec)=(d)/(t)`

(a) Now, if the animal runs for a time t = 5 seconds, we have to find what is its distance traveled, d. To do so, we solve the expression above for d by multiplying both sides by t,

`d=40(ft)/(sec)\cdot t=40(ft)/(sec)\cdot5sec=200ft`

Hence, in 5 seconds the animal travels 200 feet.

(b) For this part of the question, we have to find the other variable, t, knowing that the distance traveled is d. Since the distance is not given as a number, we will find an expression as a function of d,

`40(ft)/(sec)=\frac{d\text{ }ft}{t}`

Solving for t,

`t=\frac{d\text{ }ft}{40(ft)/(sec)}`

The unit of distance, feet, cancels out, and we have the result in seconds,

`t=(d)/(40)\text{ }sec`

Hence, the time for a distance traveled of d feet is d/40 sec.