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Help with Probability question.

Draw a sample space diagram showing all the possible combinations of scores after throwing a standard dice and spinning this spinner ( Spinner includes numbers 1-5).

Find the probability of getting a total score if at least 9.

In this question I found 3 ways so 3/30 but its wrong. Please help
1 2 3 4 5 6
1 2 3 4 5 6 7 The answer should be 3/30, which cancelled down is 1/10 or 0.1 as a decimal. What is the answer they give you?

2 3 4 5 6 7 8

3 4 5 6 7 8 9

4 5 6 7 8 9 10

5 6 7 8 9 10 11
Original post by amberfox264
1 2 3 4 5 6
1 2 3 4 5 6 7 The answer should be 3/30, which cancelled down is 1/10 or 0.1 as a decimal. What is the answer they give you?

2 3 4 5 6 7 8

3 4 5 6 7 8 9

4 5 6 7 8 9 10

5 6 7 8 9 10 11


That's exactly what I got!
The answer book said 6/30 which simplifies to 1/5.

Their are only 3 times you can get 9 in that diagram so I don't know how they got 6/30
Original post by Oneiropólos
That's exactly what I got!
The answer book said 6/30 which simplifies to 1/5.

Their are only 3 times you can get 9 in that diagram so I don't know how they got 6/30


I imagine it must be a mistake in the book. (If you use Pearson books, they’re full of mistakes haha)
Original post by Oneiropólos
That's exactly what I got!
The answer book said 6/30 which simplifies to 1/5.

Their are only 3 times you can get 9 in that diagram so I don't know how they got 6/30


Read the question. It says at least 9. That's different from exactly 9. 6/30 is correct.
Original post by TheMindGarage
Read the question. It says at least 9. That's different from exactly 9. 6/30 is correct.


^^ smart bro, you get a rep haha
Original post by TheMindGarage
Read the question. It says at least 9. That's different from exactly 9. 6/30 is correct.


I was thinking of something like that actually. But then how is 6/30 correct? What did you count and what does at least 9 mean?
Reply 7
It is possible to get a score of 9,10 or 11. At least 9 means more than 8.
Original post by Oneiropólos
I was thinking of something like that actually. But then how is 6/30 correct? What did you count and what does at least 9 mean?


At least 9 means 9 or higher (10 or 11). I just counted those which are 9 or above.

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