Pat will walk from Intersection X to Intersection Y along a route that is confined to the square grid of four streets and three avenues shown in the map above. How many routes from X to Y can Pat take that have the minimum possible length?
(A) 6
(B) 8
(C) 10
(D) 14
(E) 16
[spoiler]OA: C[/spoiler]
Source: OG-12
Can anyone suggest an easy way to solve this problem and others of such kind?
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Pat has to walk..
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knight247
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Hey Elena
All the streets and avenues are of equal length hence any route he takes will be of equal length. Its best to use the anagram method for such grid problems.
Suppose he decides the take the extreme route along the outer boundary of the grid...He has to walk
East East and then North North North. Try any random combination by urself and u'll find that every combo has two Easts and 3 Norths. So we have EENNN for short. Which can be permuted in 5!/(3!2!)=
10 Ways Hence C
All the streets and avenues are of equal length hence any route he takes will be of equal length. Its best to use the anagram method for such grid problems.
Suppose he decides the take the extreme route along the outer boundary of the grid...He has to walk
East East and then North North North. Try any random combination by urself and u'll find that every combo has two Easts and 3 Norths. So we have EENNN for short. Which can be permuted in 5!/(3!2!)=
10 Ways Hence C
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GMATGuruNY
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- GMAT Score:790
I posted a solution here:Elena89 wrote:Pat will walk from Intersection X to Intersection Y along a route that is confined to the square grid of four streets and three avenues shown in the map above. How many routes from X to Y can Pat take that have the minimum possible length?
(A) 6
(B) 8
(C) 10
(D) 14
(E) 16
[spoiler]OA: C[/spoiler]
Source: OG-12
Can anyone suggest an easy way to solve this problem and others of such kind?
https://www.beatthegmat.com/pat-and-his- ... cityevent=
Two similar problems:
https://www.beatthegmat.com/combinatroni ... 68412.html
https://www.beatthegmat.com/different-routes-t93698.html
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
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