SOLUTION: A downtown area is rectangular, 3 blocks by 5 blocks.How many ways are there to drive from one corner to the opposite corner, if you must make exactly 2 turns?
Question 548223: A downtown area is rectangular, 3 blocks by 5 blocks.How many ways are there to drive from one corner to the opposite corner, if you must make exactly 2 turns? Answer by Edwin McCravy(20054) (Show Source):
You can put this solution on YOUR website! There are just the 6 ways indicated below. Follow the red paths from the
lower left to the upper right (east), using the convention that "right is
east and up is north":
As you see above, if you go east first, there are 4 choices of streets
to turn north on. Then you must go 3 blocks north and turn right.
That's 4 ways. [Notice that you cannot go east to the last street on the
right before turning north, for you would then make only 1 turn.]
As you see above, if you go north first, there are 2 choices of streets
to turn east on. Then you must go 5 blocks east and turn north.
That's 2 more ways. [Notice that you cannot go north to the street on the
top before turning east, for you would then make only 1 turn.]
Total: 6 ways.
Edwin
