Car a and car b start together. car a travels once around a circular track at 30 mph. car b travels in the opposite direction at 20 mph until he passes car a. from this point, at what speed must car b travel to finish once around the track at the same time that car a does?

After they start, the speed at which the cars are moving toward each other is (30 mph) + (20 mph) = 50 mph. At the time they meet, Car A will have traveled 30/50 = 0.6 of the distance around the track, while Car B will have traveled the other 0.4 times the distance.

Car A will have to cover only 0.4 times the length of the track before being at the start. This is 0.4/0.6 = 2/3 of the distance Car A has already traveled, so is expected to take 2/3 of the time already taken.

Car B must cover 0.6/0.4 = 3/2 times as much track as it has already covered. In order to do so, its speed will need to be

... speed ratio = (distance ratio)/(time ratio) = (3/2)/(2/3) = 9/4

times what it has been so far.

Car B's speed will need to be

... 9/4 × 20 mph = 45 mph

to finish at the same times car A does.

from the figure we get,

the x axis shows   the months and,

the y-axis shows the number of satisfied customer.

each line or each cell in upward direction (y-axis) shows 500.

the appropriate scale for the y - axis is: -

a = 2000 customers

b = 4000 customers

c = 6000 customers

d = 8000 customers

e = 10000 customers

f = 12000 customers

g = 14000 customers