Suppose you roll two dice. What is the probability of rolling a sum of 8?

3 Answers
Jun 11, 2018

#5/36#

Explanation:

[Assuming we're dealing with #6#-sided dice]

We know we're dealing with two dice. Since each die has #6# different possibilities, the outcomes of rolling two dice are given by

#6xx6#, which is #36#. This will be our denominator.

How many ways can we get #8# with two dice?

#2+6=8#

#3+5=8#

#4+4=8#

#5+3=8#

#6+2=8#

These are all ways to get #8# with two dice. There's #5# ways, so this will be our numerator. We have

#P#(sum of #8# with two dice)=#5/36#

Hope this helps!

Jun 11, 2018

#5/36#

Explanation:

So if you have 2 dice (supposing that they are 6 sided, we know that all the possible combinations of the dice are #36# So now we have to make a process of elimination:

#2+6# / #6+2# / #3+5# / #5+3# / #4+4# ( '/' seperates numbers)

We have repeated some because (let's say a dice is #a# and the other is #b#) #a# could be #3# but #b# could also be #3#.

So if we know that there are five know combinations for rolling sum of #8# then we write it as a fraction so #5/36#

We write it over the possible outcomes because of a simple rule:

the desired outcome / all possible outcomes

Hope this helped you out!

Jun 11, 2018

#5/36#

Explanation:

Lets produce a table:
Tony B

The total count of available combined values is #6xx6=36#

Inspection of the table shows that there are 5 lots of 8 so we have:

#("red")/("green and red") ->5/36#