Flying the fast bird

Stump your fellow simians.
Skeeve
Posts: 15247
Joined: Wed Jun 09, 2004 7:35 am

Flying the fast bird

Post by Skeeve »

An old math problem that I've encountered a few times along the way goes like this:

A bird flies at 60 mph. It's an amazing bird, it always goes 60 MPH unless it's not flying. If it turns around it does so instantly. You might even say I'm flipping you the ideal bird.

Anyhow, this bird got the idea to fly from the front of a locomotive to the front of another locomotive, turn around, back to the first one, back to the second, etc, until the two locomotives pass each other.

Unfortunately, both the bird and the locomotive engineers got it wrong, they are on the same track, and they are going to crash, with the unfortunate perfect bird caught in the middle.

The two locomotives are 120 miles apart. One is moving at 15 mph, the other at 45 mph, and neither vary speed. Yes, they are moving toward each other, not away from each other.

How far does the bird fly from the time it leaves the front of locomotive 1 when they are 120 miles apart, until it's squashed between two huge locomotives?
ceptimus
Posts: 1462
Joined: Wed Jun 02, 2004 11:04 pm
Location: UK

Post by ceptimus »

Spoiler. (Ctrl-A to view)

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Converging speed of locos is 45 + 15 = 60 mph or one mile a minute.

They start 120 miles apart so will collide in two hours or 120 minutes.

The bird also covers one mile a minute, so it will cover 120 miles before getting squished.

</td></tr></table>
DanishDynamite
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Joined: Mon Jun 07, 2004 4:58 pm
Location: Copenhagen

Post by DanishDynamite »

The two trains are approacing each other at 15 + 45 MPH = 60 MPH. They are 120 miles apart. They will therefore meet after 2 hours.

The bird flies continuosly at 60 MPH. In 2 hours it will fly therefore fly 120 miles.
DanishDynamite
Posts: 2608
Joined: Mon Jun 07, 2004 4:58 pm
Location: Copenhagen

Post by DanishDynamite »

ceptimus sucks! :x :D
Skeeve
Posts: 15247
Joined: Wed Jun 09, 2004 7:35 am

Post by Skeeve »

DanishDynamite wrote:The two trains are approacing each other at 15 + 45 MPH = 60 MPH. They are 120 miles apart. They will therefore meet after 2 hours.

The bird flies continuosly at 60 MPH. In 2 hours it will fly therefore fly 120 miles.

Exactly. Now, what a skinny little math geek would do is write an absolutely mind-boggling summation. I won't even try to reproduce it here. I won't even try to reproduce it anywhere. I can't.

That's the difference between adult wisdom and raw ability.
En folkefiende
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Joined: Thu Aug 12, 2004 4:38 am
Location: Waiting for an electrician

Post by En folkefiende »

Skeeve wrote:
DanishDynamite wrote:The two trains are approacing each other at 15 + 45 MPH = 60 MPH. They are 120 miles apart. They will therefore meet after 2 hours.

The bird flies continuosly at 60 MPH. In 2 hours it will fly therefore fly 120 miles.

Exactly. Now, what a skinny little math geek would do is write an absolutely mind-boggling summation. I won't even try to reproduce it here. I won't even try to reproduce it anywhere. I can't.

That's the difference between adult wisdom and raw ability.

Um, hmmm, even skinny little math nerds can learn new tricks. I think you're about to get a PM, I do, I do.