Connect with a global community of knowledgeable individuals on IDNLearn.com. Our platform is designed to provide quick and accurate answers to any questions you may have.

The distance between two cities is 180 km. The distance was
covered by a car at a rate of 50 km/h, by a bus at 45 km/h, by a
truck at 40 km/h, and a by a bicycle at 25 km/h. What is the constant of
variation?


Sagot :

Answer:

Step-by-step explanation:

he distance between two cities is 180 km.

Speed = distance/time

v = s/t from this we can calculate for time  

Time = distance /speed

This distance was covered by a car at a rate of 50 km/h

Time taken by the car to cover this distance of 180km

= 180/50 = 3.6 hours  

This distance was covered by a bus at 45 km/h

 

Time taken by the bus to cover this distance of 180km

= 180/45 = 4 hours

This distance was covered by a truck at 40 km/h

Time taken by the truck to cover this distance of 180km

= 180/40 = 4.5 hours

This distance was covered by a bicycle at 25 km/h

Time taken by the truck to cover this distance of 180km

= 180/25 = 7.2 hours

Therefore:

speed and time are directly proportional.

Speed, s is inversely proportional to time, t

xy = k (inverse variation) or y/x = k (direct variation), where k is the constant of variation

Introducing constant of variation, k  

s = k/t  

When s = 25, t = 7.2

25 = k/7.2

k = 7.2× 25 = 180

So

s = 180/k