Three Ball Line Up

Stage: 1 Challenge Level: Challenge Level:2 Challenge Level:2

We received many solutions to this problem, but Charles from Clear Water Bay School in Hong Kong, Alex from Longsands School and Maria from Wimbledon High Junior School took the trouble to explain how they worked it out. Charles says:

The answer is $6$.
If the green ball is in the first place, there are two combinations i.e. red ball second, blue ball third or blue ball second, red ball third.
That gives us two ways if the green ball lands in the first place.
It is the same with the other two balls. Therefore, $3 \times 2 = 6$ ways.

Here are the ways that all three of them listed:

green, red, blue
green, blue, red
blue, red, green
blue, green, red
red, blue, green
red, green, blue

Published November 2005,December 2005.