Question

You roll 1 red and 1 blue die. What is the probability that the number on the red die is the same as the number on the blue die?

Answer 1

how many possibilities do you have on either die?

Answer 2

6?

Answer 3

yup, do you know how to draw a probabilities diagram?

Answer 4

no, i just started probability last week.

Answer 5

kwlio, well this would be the diagram for a similar question.

What is the probability of you rolling a 1 on the first dice and a 2 on the second dice.

now the first roll has a 1/6 chance to be a 1, the second roll also has a 1/6 chance to be a 2. But to get the probability of both at the same time you multiply the two probabilitys together to get a probability of 1/36 to get a 1 then a 2.

Answer 6

understand so far?

Answer 7

yes i think so

Answer 8

ok now with your problem, what is the probability of the first dice roll being a certain number?

Answer 9

1/6?

Answer 10

yup, and what is the probability of the second dice roll being another certain number?

Answer 11

1/6?

Answer 12

yes, but you want the probability of it being the same number. So say those numbers you rolled are the same, what would their final probability be if when rolling the dice you have a 1/6 chance to roll a number on each dice?

Answer 13

would it be 1/36? or 2/36?

Answer 14

the first one.

Answer 15

did that help?

Answer 16

yes, thanks.

Answer 17

any more help needed?