Question

Two fair die are rolled. (1) What is the probability they sum to 10, 7, or 4? (2) What is the probability they sum to at least 11?

Answer 1

So for two dices, there are 6*6 = 36 possible combinations right?

Answer 2

yes

Answer 3

how many combinations add up to 4?

Answer 4

2

Answer 5

1,3
3,1
2,2
there are 3

Answer 6

okay

Answer 7

so for 4, it is 3/36 = 1/12

Answer 8

correct

Answer 9

so you can do the same for 7 and 10 to for (1).

Answer 10

are you saying that there are 6 ways to add up to 6?

Answer 11

yes, so its probability is 1/6

Answer 12

btw how did you get 1/12 for 4?

Answer 13

sorry sorry no there's 5 ways to add up to 6

Answer 14

1,5
2,4
3,3
4,2
5,1

Answer 15

The number is seven my bad

Answer 16

Oh yes

Answer 17

can you explain how you got 3/36 though for 4?

Answer 18

3 combinations to get 4 / all the possible combinations = 3/36.

Answer 19

how is it 36 though

Answer 20

there are 6 possibilities on the first dice & 6 possibilities on the second dice.
6 * 6 = 36

Answer 21

oh never mind. sorry I didn't think about that, I've had a really long day. You are right

Answer 22

oh ok! :D

Answer 23

so in total it should be 6/36+3/36+3/36=12/36=1/3

Answer 24

and for (2), you just have to find the probability that the sum is 12
and subtract it from 1

Answer 25

and yes

Answer 26

why subtract one for the sum is 12?

Answer 27

at least 11 is the same as not 12, becuase the biggest sum is 12

Answer 28

right. So that means 11 and 12?

Answer 29

so, "at least 11" refers to sums 2-11. so the only sum that is not considered is 12.

Answer 30

oh

Answer 31

do you get that?

Answer 32

so what you have to do is
1 - (probability of getting 12) = probability of all sums at least 11

Answer 33

so is that mean the answer is 35/36?

Answer 34

yes :D

Answer 35

it says 35/36 is wrong but the first answer is right

Answer 36

really? :,o let me think I'm sorry...

Answer 37

its okay

Answer 38

AHHH I READ THE PROBLEM WRONG...
YOU WERE RIGHT IT IS PROBABILITY OF 11 AND 12

Answer 39

so its 1/12

Answer 40

I CAN'T BE MORE SORRY THAN THIS SORRY

Answer 41

YES

Answer 42

dude its alright

Answer 43

That was right

Answer 44

:D thank you very much

Answer 45

thank you :)