I am stuck on this...

Q: If you roll 3 dice, what is the probability that the product of the 3 numbers will be a prime number (1,3,5,7,11,17) ?

Thanks for the help!

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- Mar 23rd 2010, 05:20 PMFiahDice probability question
I am stuck on this...

Q: If you roll 3 dice, what is the probability that the product of the 3 numbers will be a prime number (1,3,5,7,11,17) ?

Thanks for the help! - Mar 23rd 2010, 05:41 PMpickslides
Make a Lattice or Tree diagram and count the results that give a prime.

- Mar 23rd 2010, 06:14 PMFiah
I got 5/108 ... does that sound right?

- Mar 23rd 2010, 09:46 PMmr fantastic
- Mar 23rd 2010, 10:09 PMFiah
In this context, I considered '1' as a prime, I know it is not a true prime number. I did forget to put 2 in my prime number list, my mistake..

...(4/6)(1/6)(1/6) + (1/6)(3/6)(1/6)+ (1/6)(1/6)(3/6)

...4/216 + 3/216 + 3/216

...10/216 (reduce)

...5/108

That's how I got 5/108