Problem Solving

is there a really fast way of solving PS problem #195 from OG 11ed ?
pat walks from intersection X to intersection Y problem ?

Thnx,
-Badri

No one is going to look up the question to help you. If you want help, at least be active enough to type out the question.

..Seriously dude .. the least u can do is type out the question .. plz do not expect people to go and fetch the question for u and then respond to your queries ..

Yeah. And do not even get me started on ones who post screen shots for problems with plain text...

sorry folks. the problem had a figure which I couldn't draw very easily. Hence the pointer to the problem.
Will write up the whole problem and try to draw the figure once I get home tonight.

-B
P.S. From what I remember-
imagine a 1st quadrant grid. How many different shortest paths are possible from (0,0) to (3,4) travelling only along the grid lines (going from y=0 to y=4, x=0 to x=3
I'll confirm this evening.

I remember this question... I believe the answer was 10?

By taking the shortest route possible, he can only travel Up (U) three or Right (R) two.

The combinations are:

UUURR
UURRU
URRUU
RRUUU
UURUR
URURU
RURUU
URUUR
RUURU
RUUUR

In other words:

5!/3!*2!

here..lemme post the question

beny, one question----what does 5! denote...........

The combinatoric way to solve this question is the "anagram approach". In other words, how many words can you make with a set of letters via rearranging the letters. The way to figure this out is:

(Total number of letters)! / (Number of each repeating letter)!

Here, the total number of letters is 5, there are 2 repeating R's and 3 repeating U's.

got it.....thnkx