How many ways can you roll two standard number cubes and get a sum of 9??please show steps of how you solved.?

Answer 1

6 and 3, 5 and 4, 4 and 5, 3 and 6.....that's it....so 4 ways

Answer 2

Possible 9 combinations are 6+3, 5+4, 4+5 and 3+6. This is 4 ways out of the total 36 combinations (6 per die so 6*6 = 36). So there are 4 possible combinations out of the total of 36, or about an 11% chance of getting a 9.

Another way you could do it would be to write out all the possible combinations (1-1, 1-2, 1-3, etc.) and then count the ones that add up to 9. Above is just a short cut.

Answer 3

4 ways

Answer 4

The sample space of either die is {1,2,3,4,5,6}

Now clearly both numbers rolled must be in {1,2,3,4,5,6} so we need to enumerate all possibilities such that x1 + x2 = 9; x1 in {1,2,3,4,5,6} and x2 in {1,2,3,4,5,6}

Its not hard to see that you have

(x1,x2)={3,6} or {4,5} or {5,4} or {6,3}

Which is 4 ways.