# Thread: Odds with 2 normal dice and 1 unusual?

1. ## Odds with 2 normal dice and 1 unusual?

Hello,
I am trying to find the odds/probability of rolling all three dice and it resulting in a Double:

a) Two regular dice with 1,2,3,4,5,6 on the faces
b) A third six sided dice with the following on the faces: 1,blank,blank,blank,6,6

My math skills are poor, so any help would be appreciated.

2. Originally Posted by jackbo
Hello,
I am trying to find the odds/probability of rolling all three dice and it resulting in a Double:

a) Two regular dice with 1,2,3,4,5,6 on the faces
b) A third six sided dice with the following on the faces: 1,blank,blank,blank,6,6

My math skills are poor, so any help would be appreciated.

List the possibilities. Calculate the probability for each possibility. Add up the probabilities.

If you need more help, please show your work and say where you get stuck.

3. Okay, I have the following possibilities:
Dice
a: b: c:
1 1 x
1 x 1
x 1 1
2 2 x
3 3 x
4 4 x
5 5 x
6 6 x
6 x 6(y)
x 6 6(y)
6 x 6(z)
x 6 6 (z)

So, it's possible to get 12 doubles. I am probably coming across here as a thicko, I just cannot do maths, so I am not sure how to work out the probability and odds.

4. Originally Posted by jackbo
Okay, I have the following possibilities:
Dice
a: b: c:
1 1 x
1 x 1
x 1 1
2 2 x
3 3 x
4 4 x
5 5 x
6 6 x
6 x 6(y)
x 6 6(y)
6 x 6(z)
x 6 6 (z)

So, it's possible to get 12 doubles. I am probably coming across here as a thicko, I just cannot do maths, so I am not sure how to work out the probability and odds.
If you have been given this question to do then surely you know something about probability and how to calculate it.

Since you have named the dice a, b and c and listed the outcomes for each, clearly the red events I highlighted are NOT included. You need to think carefully why ( I suggest you consider what happens with only two dice to understand this). You have listed other events - which I haven't highlighted - which should also NOT be included. It is your job to get an accurate list.

The probability of the event (1, 1, x) is (1/6)(1/6)(4/6) = .....

Other events are similarly calculated.

Then you add up the probabilities to get a total probability.