Question

There are six roads between A and B and four roads between B and C.
a) In how many ways can on drive from A to C by way B?
b) In how many ways can one drive from A to C by way of B?
c) In how many ways can one drive round trip A to C without using the same road?

Answer 1

b) In how many ways can one drive ROUNDTRIP from A to C by way of B?

Answer 2

Use the Counting Principle...if one event can occur m ways, and a second event can occur n ways, then the total number of ways both events can occur, is m(n).

Answer 3

is that something like P(m, n) = n! / (n-r)!

Answer 4

No. If there are 5 roads from A to B, and 8 roads from B to C, then the total number of roads from A to C (via B) is 5 x 8 = 40.

Thats an application of the Counting Principle.

Answer 5

ok thank you. do you happen to know when that formula i just showed should be used by chance?

Answer 6

You can look online under "Counting Principle". But if you understand what I just showed you, then you should be able to answer the questions.

Answer 7

ok thanks

Answer 8

welcome.