Page 98 - NUMINO Challenge_B2
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Basic Concepts Number of Shortest Paths
The fastest way to get from one point to another is called A
the shortest path. In the figure on the right, the shortest
path from A to B is to go only to the right or down.
B
To find the shortest path from A to B, first write 1 where there is only
one path. Then, add the paths that come from the left and from
below, and write the sum.
A 111 A 111
1 1 23 4
1 1 3 6 10
1 1 4 10 20
BB
Example Find the number of shortest paths from A to C if you must pass
through B.
A
B
C
Class Notes shortest paths from A to B. 1 11
A
There are 1234
1 3 6 10
There are shortest paths from B to C.
B
There are shortest paths from A to C.
B
C
95Number of Outcomes
The fastest way to get from one point to another is called A
the shortest path. In the figure on the right, the shortest
path from A to B is to go only to the right or down.
B
To find the shortest path from A to B, first write 1 where there is only
one path. Then, add the paths that come from the left and from
below, and write the sum.
A 111 A 111
1 1 23 4
1 1 3 6 10
1 1 4 10 20
BB
Example Find the number of shortest paths from A to C if you must pass
through B.
A
B
C
Class Notes shortest paths from A to B. 1 11
A
There are 1234
1 3 6 10
There are shortest paths from B to C.
B
There are shortest paths from A to C.
B
C
95Number of Outcomes
