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#1 2009-03-08 07:20:59
- kgh
- Member
- Registered: 2009-02-08
- Posts: 11
Related rates problem
Car A is traveling north at 80 km/hr and car B is traveling west at 110 km/hr. Both are headed for the intersection of the two roads. At what rate are the cars approaching each other when car A is 0.4 km and car B is 0.7 km from the intersection?
I solved this problem and I think I have the correct answer, but I would love some validation!
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#2 2009-03-08 08:06:46
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Related rates problem
I get that A is approaching B at ~39.69 km/h and B is approaching A at ~95.51 km/h.
Therefore, they are approaching each other at ~135.20 km/h.
(Thankfully, they don't crash. 
)
Why did the vector cross the road?
It wanted to be normal.
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#3 2009-03-08 08:10:34
- kgh
- Member
- Registered: 2009-02-08
- Posts: 11
Re: Related rates problem
Perfect! That's approximately the answer I got as well. Thanks a lot!
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