A red number cube and a blue number cube are rolled. If all numbers are equally likely, what is the probability that the number on the red cube is greater?
1 Answer
Sep 2, 2016
Explanation:
The clearest way to work this out is with a possibility space.
"Y" indicates that the value on the red is greater than on the blue.
There are
For 6 of these, the values are the same, when a 'double' is thrown.
For the 30 outcomes that are left, in half of them, the red value is more, and in half of them the blue value is more.
The 15 outcomes where red > blue are shown above.