Probability question involving poker machines - need help (1 Viewer)

[blackops23]

Hi guys, maybe its because I don't have enough experience on the poker machines, but I'm having a bit of trouble with this question, even though it's a simple 2u question.

Q. On a three-wheel poker machine, there are 10 symbols on each wheel.
There are:
5 lemons on the first wheel.
3 lemons on the 2nd wheel.
2 lemons on the last wheel.


(b) What is the probability that the 2 outside wheels will show a lemon with something different on the middle wheel.


I got P(LNL) = 7/100, where L is the lemon, and N is no lemon.

I got this because:
P(LNL) = P(lemon on wheel 1) * P(no lemon on wheel 2) * P(lemon on wheel 3)
= 0.5 * 0.7 * 0.2
= 0.07

But the answer was P(E) = 1/10 = 0.1

So why did I get 0.07, while the answer was 0.1, did I misinterpret the question or did I do some error in my working?

Help greatly appreciated,

Thanks

 

[mitchy_boy]

The answer could be wrong. My text book was always wrong for probability. What you've done seems right to me, although this was my worst topic in 2unit...

 

[blackops23]

Anyone else got anything, perhaps if I did something wrong, or misunderstood the question?

 

[Bored Of Fail 2]

your answer looks correct

 

[blackops23]

your answer looks correct

So it's a problem on behalf of Jones and Couchmann? Because this is the first mistake I've seen in the book...

 

[Bored Of Fail 2]

So it's a problem on behalf of Jones and Couchmann? Because this is the first mistake I've seen in the book...

quite possibly its a mistake, I dont really know where they could have got 1/10 :S and its not like a question involving arrangements , there is only one way to get what they are after in the problem statement