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Every hour, on the hour, a bus leaves town A and heads toward town B.

Every hour, on the hour, another bus leaves town B and heads toward town A.

The trip between the two towns takes exactly two hours.

How many buses going from town A to town B will the people on a bus going from town B to town A SEE during their trip?

Note: All buses are on time leaving and arriving.

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You can't be certain as you don't control all bus services

:D

Three, observing the given information. If you will see one at the midpoint and one three quarters through, it stands to reason, another bus will pass you at your one quarter mark.

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No he is not. Three is a minimum possible. Most likely 4 but could also be five.

Hi Brenflansd42,

I was just going by this question: "How many buses going from town A to town B will the people on a bus going from town B to town A SEE during their trip?"

This is my reasoning: The two towns are 2 hours apart. Therefore, both towns are in the same time zone. Suppose at 1 o'clock, the 1 o'clock bus from town A is heading out to town B, and at the same 1 o'clock time the 1 o'clock bus from town B is heading out to town A. The question is when will the people on the 1 o'clock from town B see the 1 o'clock bus from town A? Naturally, the two buses will pass each other one hour later or at 2 o'clock in the middle of the way. So right there, the people from town B will see 1 bus coming from town A. However, at 2 o'clock, the 2 o'clock bus from town A will also be leaving for town B. When then will the people on the 1 o'clock bus from town B see the 2 o'clock bus from town A? It is exactly 30 minutes later. So then the people will be seeing 2 busses from town A. Finally, 2 hours later when 1 o'clock bus from town B has reached it destination at town A, the 3 o'clock bus from town A is on its way to town B. So the people on the bus from town B will see a total of 3 busses leaving from town A. I could be wrong though.

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wait a min folks!

NuttyNumbers said a trip between two towns, now it could also mean a round-trip.

Let's say you leave at hour T from Town B then you'll see following buses from Town A:

  1. The bus that left at hour T-2, would approach just when you are leaving.
  2. The bus that left at hour T-1, would meet you at 1/4 distance from Town B.
  3. The bus that left at hour T, would meet you mid way.
  4. The bus that left at hour T+1, would meet you at 3/4 distance from Town B.
  5. The bus that would leave at hour T+2 would just be leaving when you arrive.

Thus, assuming constant speed and time for boarding/alighting the number is 5.

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wait a min folks!

NuttyNumbers said a trip between two towns, now it could also mean a round-trip.

Let's say you leave at hour T from Town B then you'll see following buses from Town A:

  1. The bus that left at hour T-2, would approach just when you are leaving.
  2. The bus that left at hour T-1, would meet you at 1/4 distance from Town B.
  3. The bus that left at hour T, would meet you mid way.
  4. The bus that left at hour T+1, would meet you at 3/4 distance from Town B.
  5. The bus that would leave at hour T+2 would just be leaving when you arrive.

Thus, assuming constant speed and time for boarding/alighting the number is 5.

Urmmm.....isn't that what I said?

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Hi Brenflansd42,

I was just going by this question: "How many buses going from town A to town B will the people on a bus going from town B to town A SEE during their trip?"

This is my reasoning: The two towns are 2 hours apart. Therefore, both towns are in the same time zone. Suppose at 1 o'clock, the 1 o'clock bus from town A is heading out to town B, and at the same 1 o'clock time the 1 o'clock bus from town B is heading out to town A. The question is when will the people on the 1 o'clock from town B see the 1 o'clock bus from town A? Naturally, the two buses will pass each other one hour later or at 2 o'clock in the middle of the way. So right there, the people from town B will see 1 bus coming from town A. However, at 2 o'clock, the 2 o'clock bus from town A will also be leaving for town B. When then will the people on the 1 o'clock bus from town B see the 2 o'clock bus from town A? It is exactly 30 minutes later. So then the people will be seeing 2 busses from town A. Finally, 2 hours later when 1 o'clock bus from town B has reached it destination at town A, the 3 o'clock bus from town A is on its way to town B. So the people on the bus from town B will see a total of 3 busses leaving from town A. I could be wrong though.

is that you're forgetting the buses that left 'A' before 1 o' clock. i.e. 11 & 12 oclock buses will also be seen by people on 1 oclock bus from 'B'

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is that you're forgetting the buses that left 'A' before 1 o' clock. i.e. 11 & 12 oclock buses will also be seen by people on 1 oclock bus from 'B'

Yes, I saw that when I looked at it today as well. You are correct.

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is that you're forgetting the buses that left 'A' before 1 o' clock. i.e. 11 & 12 oclock buses will also be seen by people on 1 oclock bus from 'B'

Yes, I see it now. You are in the right, and I am convinced of your thoughtful answer. I stand corrected.

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5 (6 if you include the one they're on)

say you're on the 6 oclock bus at 'A'

the 4 oclock bus from'B' will be pulling in

When you arive at 'B', the 8 oclock bus will be pulling out

therefore buses from 'B' at 5 6 and 7 oclock will have passed you.

New poster Here. I totally agree with the assumption Bus A will see Bus B pulling in and on arrival as well as the 30 minute interval observation.

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