Maze Problem?

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Maze Problem?

by rajatvmittal » Mon Mar 12, 2012 7:27 am
a) If you are required to walk from intersection A
to intersection B along a route that is confined
to the square grid of four avenues and three
streets shown in the map above, how many
routes from A to B can you take that have the
minimum possible length ?

What if 4 avenues and 4 streets.

What if 5 avenues and 3 streets

What if 4 avenues and 5 streets?

Just want to know method to calculate???
Source: — Problem Solving |

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by Neo Anderson » Mon Mar 12, 2012 9:07 am
If you are required to walk from intersection A
to intersection B along a route that is confined
to the square grid of four avenues and three
streets shown in the map above, how many
routes from A to B can you take that have the
minimum possible length ?
number of avenues and streets are given, you only have to arrange them in different order, when you know total number of avenues and streets to reach the destination is also unique.
as in: say avenues (A) are 4 and streets(3) are 3
just have to arrange AAAASSS in various ways, thus 7!/(4!x3!) = 35 ways

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by rajatvmittal » Mon Mar 12, 2012 9:12 am
What if 4 avenues and 4 streets. : - Is it 8!/4!*4!

What if 5 avenues and 3 streets : - is it 8!/5!*3!

What if 4 avenues and 5 streets? : - is it 9!/5!*4!
Am i Right?

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by Neo Anderson » Mon Mar 12, 2012 9:13 am
absolutely right!