Question

9. Two towns A and B are connected by a regular bus service with a bus leaving in either direction every T minutes. A man cycling with a speed of 20 km/h in the direction A to B notices that a bus goes past him every 18 min in the direction of his motion and every 6 min. in the opposite direction. What is the time period T of the bus service and with what speed(assumed constant) do the buses ply on the road?

Answer 1

cnfused

Answer 2

Let the bus travel at a speed s. Then the distance between the buses going from A to B is
sT

Now, if the man sees them every 18 minutes, how far has he travelled in 18 minutes?

Answer 3

st/something

Answer 4

hey wait

Answer 5

He has travelled
speed . time
= 20 km/hr . 18/60 hr = 20 . 6/20 km
= 6 km.


Now for buses going from A to B, what is their velocity relative to the man?

Answer 6

oh i got that part

Answer 7

:)

Answer 8

20-s

Answer 9

james its 1:30 am here i am sleepy

Answer 10

It is s - 20.

Given that, find an equation that relates the speed of the bus s and the time T.

Now find another equation for the buses traveling from B to A.

If you do, you'll have equations in two unknowns---s and T---which you can now solve.

===

Come back in your morning then.

Answer 11

k thanx

Answer 12

I'll give you the first one. In the 18 minutes = 3/10 hour, the bus travels a distance of 3s/10.

Now at the moment that one bus passes the man, the next bus has to travel a distance of
sT + 6 to catch up. Draw yourself a diagram and convince yourself of all that.

In which case: sT + 6 = (3/10)s