IDNLearn.com is the perfect place to get answers, share knowledge, and learn new things. Join our community to access reliable and comprehensive responses to your questions from experienced professionals.

6. It takes a delivery truck 2 hours to travel 70 km to deliver a new fridge. The truck drives part of
the way on the highway at 80 km/h and the rest on city roads in traffic at only 20 km/h. (6 marksT)
a) How far did the truck travel on each road?
4


Sagot :

Answer:

40 km on the highway

30 km on the city roads

Step-by-step explanation:

Let x = highway

Let y = city road

The time formula: time = distance / speed.

1) Since we do not know the distance travelled on the highway and city roads but we do know the total time taken, we can say x + y = 70. Set the distances x and y and all equated to 2 hours, since we do not know them, nor do we know the time. This is called a system of equations.

x + y = 70

x/80 + y/20 = 2

2) Solve the system of equations using substitution.

x = 70 - y

---------------

70 - y/80 + y/20 = 2

70 + 3y/80 = 2

y = 30

---------------------------------

x + 30 = 70

x = 70 - 30

x = 40

Therefore, the delivery truck travelled 40 km on the highway and 30 km on the city roads.