Page 97 - NUMINO Challenge_B2

11 Number of Shortest Paths

Basic Concepts Finding the Number of Ways

There are three rails and two roads connecting Rail
town A and town B. Therefore, there are 3 2 5 Rail
Rail

ways to go from A to B. AB

There are 3 2 6 ways to go to a town by rail Road

and return by road. Road

Example Tom has four different shirts and three different pants. How many
outfits can Tom have? If Tom wants to give one piece of clothing
to a friend, how many ways are there to do this?

Class Notes

Tom has different shirts and different pants. Therefore, Tom has
4 different outfits.

There are four different shirts and different pants that Tom can give to a friend.

Therefore, there are 4 different ways Tom can give one piece of clothing
to a friend.

Try It Again Find the number of shortest paths from A to C if you must
pass through B.

ABC

94 NUMINO Challenge B2