# die probability

• Mar 18th 2008, 04:36 PM
leotay
die probability
Linda has a special pair of dice. each die has sides labeled 2,3,5,7,12, and 15 respectively. she rolls the pair of dice and finds the sum of two numbers.

A) What is the probability that the sum is even?

B) What is the probability that the sum will be less than 20?

can u help me figure out this problem please!!
• Mar 18th 2008, 04:59 PM
Soroban
Hello, leotay!

With dice problems, we must simply list the outcomes.

Quote:

Linda has a special pair of dice.
Each die has sides labeled 2,3,5,7,12, and 15.
She rolls the pair of dice and finds the sum of two numbers.

A) What is the probability that the sum is even?

B) What is the probability that the sum will be less than 20?

Here are the thirty-six outcomes . . .

. . $\displaystyle \begin{array}{c|cccccc} + & 2 & 3 & 5 & 7 & 12 & 15 \\ \hline 2 & 4 & 5 & 7 & 9 & 14 & 17 \\ 3 & 5 & 6 & 8 & 10 & 15 & 18 \\ 5 & 7 & 8 & 10 & 12 & 17 & 20 \\ 7 & 9 & 10 & 12 & 14 & 19 & 22 \\ 12 & 14 & 15 & 17 & 19 & 24 & 27 \\ 15 & 17 & 18 & 20 & 22 & 27 & 30 \end{array}$

Got it?

• Mar 18th 2008, 05:09 PM
leotay
Thanks that's what we did but I wasn't sure it was correct. So how would you state the answer. Can you just state it as a fraction 20/36 the sum would be even and then 29/36 the sum would be lower than 20. Again thank you so much for all of your help. It is greatly appreciated. From a formly frustrated mom.