Determine the probability of not rolling a perfect square..

[lisa.]

Determine the probability of not rolling a perfect square with two dice.

I drew a tree diagram for this one:

Thanks for the help!

 

[pka]

The only three squares one can roll with two dice are: 4, 9.
You can roll 4 in three ways; 9 in four ways.

 

[soroban]

Re: Determine the probability of not rolling a perfect squar

Hello, lisa!

Determine the probability of not rolling a perfect square with two dice.

You found the probability of not rolling a "double".

The only squares that can be rolled are: \(\displaystyle 4\) and \(\displaystyle 9\).

Of the 36 outcomes,
. . "4" can be rolled in 3 ways: (1,3), (2,2), (3,1)
. . "9" can be rolled in 4 ways: (3,6), (4,5), (5,4), (6,3)

There are \(\displaystyle 7\) ways to roll a square.
. . Hence, there are: \(\displaystyle \,36\,-\,7\:=\:29\) ways to not roll a square.

Therefore: \(\displaystyle \,P(\text{not square}) \:=\:\L\frac{29}{36}\)

 

[lisa.]

Thank you for the help guys

Lisa