Question

HELP:
Two number cubes are rolled --one blue and one yellow. Find the probability that the blue cube is less than 3 and the product is 8.

Answer 1

What numbers that could be rolled would multiply to 8?

Answer 2

2 and 4

Answer 3

Right, and since the blue one has to be less than 3, you need to get the 2 on the blue one and the 4 on the yellow one.
That is a pretty strict outcome.

Answer 4

What are the chances of getting a 2 on one and a 4 on the other?

Answer 5

1/6?

Answer 6

Yep, and that's for each of them, so since you need both, you multiply each probability together.

Answer 7

so it wouls be 2/12?

Answer 8

No, 2/12 = 1/6; you need to find 1/6 × 1/6.

Answer 9

what my bad it's 1/36(:

Answer 10

There ya' go.

Answer 11

Thanks!

Answer 12

Sure.
As a general rule, whenever you see "probability of 'this' AND 'that'" - you multiply the independent probabilities together.

Answer 13

okay, thank you for that tip! I'll be sure to remember that!

Answer 14

You're welcome. For more on probability (probably more than you need right now):
http://stattrek.com/probability/probability-rules.aspx?Tutorial=AP

Answer 15

thank you.