Question

Check my answer on this probability question, please!
Q. Two number cubes, a red one and a blue one, are rolled. What is the probability that the red cube will be less than 4 while the blue cube if greater than 4?
My answer: 18/36 * 2/6 = 36/216. reduced: 1/6

Answer 1

looks good to me

Answer 2

This problem cannot be solved. We are not told what numbers are on the cubes. had you said a "Standard Die", we could have done it.

Answer 3

@tkhunny The cube is a typical dice. Therefore it has 6 sides

Answer 4

It doesn't say that. It cannot be assumed unless it is stated elsewhere in your assignment or course materials.

If it is so, your result is okay, but weird. The two rolls are independent. Why would you bother to use 18/36 when there are only 6 possible outcomes for the red cube and only 1, 2, 3 are possible successes? If I were grading your paper, I'd circle the 18/36 and ask why you did that.

Answer 5

@tkhunny you total confused me. I did 18*38 because they were rolled at the same time and there were 18 possibilities for the red cube to be greater than four out of the 36 total possibilities. If they were rolled on different times I would've done it seperately. I then did 2/6 because there was 6 probabilities to land on the red cube number being less 4 AND the blue cube being greater than 4. I don't even remember how I got the 2.

Answer 6

Not really. YOU actually confused you and then softball confirmed the confusion.

It doesn't matter that they were rolled at the same time. The rolls are 100% independent. It has nothing to do with 36. No one is asked to add the two die.

One die is something/6 and the other die is something/6. Oddly, you sort of recognized this with the blue die.

With your answer, ": 18/36 * 2/6 " You SAY you were rolling at the same time with "18/36", but then you forgot you already rolled the blue one and rolled it again, "2/6". It just doesn't make sense.

Answer 7

Plus, your problem statement DOES NOT say they are rolled st the same time. You can't just make stuff up.

Answer 8

OKAY JEEZ sorry for making a mistake that's why I asked here for someone to check before I turned it in. You said I got it write either way, right? I don't think the method matters as long as I got it right.

Answer 9

There is no harm in making such mistakes as long as you learn.

The method matters. This is part of learning.

Answer 10

Okay, well thanks.