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1. (Original post by 002)
How can the answer to the last part of the question possibly be 27?! If it was 27, the probability used would be 0.675. With this probability, is would have been impossible to answer the binomial distribution question which went before it, as 0.675 is not on the binomial tables, whereas 0.35 is (0.35 x 40= 14). Sorry to break it to you guys, but 14 is clearly the correct answer to the last part of question 3.
The question before it had a different probability...
3 a (iv): "at least their reserve prices but not their lower price estimates" p=0.35
3 b: "at least their reserve prices but not their upper price estimates" p=0.675
2. (Original post by Son234)
Here's my exact answers to question 3

I can categorically say the answer to part b in question 3 is 27 not 14

I lost 2 marks but i have shown the answer anyway

This was posted from The Student Room's iPhone/iPad App
yup, got that

Is it confirmed that it is 27 and not 28 like a couple other people said?

I did hardly any working as I used the graphical calculator...I'm just hoping I haven't made any silly mistakes.
3. (Original post by 002)
How can the answer to the last part of the question possibly be 27?! If it was 27, the probability used would be 0.675. With this probability, is would have been impossible to answer the binomial distribution question which went before it, as 0.675 is not on the binomial tables, whereas 0.35 is (0.35 x 40= 14). Sorry to break it to you guys, but 14 is clearly the correct answer to the last part of question 3.

This was posted from The Student Room's iPhone/iPad App
4. (Original post by 002)
How can the answer to the last part of the question possibly be 27?! If it was 27, the probability used would be 0.675. With this probability, is would have been impossible to answer the binomial distribution question which went before it, as 0.675 is not on the binomial tables, whereas 0.35 is (0.35 x 40= 14). Sorry to break it to you guys, but 14 is clearly the correct answer to the last part of question 3.
It was 27. Your claim relies on the fact that the above events were mutually exclusive, but they weren't.
An antique could fall into more than one category (e.g. Sold above reserve, sold above lower estimate). So yes, the probabilities did add up to more than one, but that's indifferent.
5. (Original post by SamuelJ)
It was 27. Your claim relies on the fact that the above events were mutually exclusive, but they weren't.
An antique could fall into more than one category (e.g. Sold above reserve, sold above lower estimate). So yes, the probabilities did add up to more than one, but that's indifferent.
I don't know about you guys, but I'm trusting the wise words of Samuel Jackson

6. (Original post by Gotzz)
I think for the CLT, all we had to say was that it was a normal distribution.
I put that the sample size was small i.e. n<30
So the central limit theorem didn't apply. But there was one past paper I did that didn't accept sample size as a reason
7. (Original post by MrJiggly)
I don't know about you guys, but I'm trusting the wise words of Samuel Jackson

It's definitely 27.
8. Yay if it is 27 lol
9. How do you question 2b and 2c?
10. (Original post by the_googly)
How do you question 2b and 2c?
find the corresponding z value for 0.98, then use the standardising equation.
And for part c, you find the z value for 0.99 (1-0.01) and put a minus sign in front of it, and then use the standardising equation again.
11. Here's my exact answers to question 2

I think they are all right but correct me if I'm wrong

This was posted from The Student Room's iPhone/iPad App
Attached Images

12. (Original post by Son234)
Here's my exact answers to question 2

I think they are all right but correct me if I'm wrong

This was posted from The Student Room's iPhone/iPad App
For part c, I used the negative z value. Because I thought it didn't make sense for the probability of X<410 to be only 0.01 if the mean is 403.
So the value I got was around 417.
13. (Original post by EmilyC96)
Venn diagram?
I think he Must be talking about other paper with coursework SS1A or wrong exam board.
14. So.... last question

"each bag"... I went with that meaning "all"... but I didn't know?
15. (Original post by Son234)
Here's my exact answers to question 2

I think they are all right but correct me if I'm wrong

This was posted from The Student Room's iPhone/iPad App
Exactly the same as me!
16. (Original post by Son234)
Here's my exact answers to question 2

I think they are all right but correct me if I'm wrong

This was posted from The Student Room's iPhone/iPad App
403 can not be the mean... think about it... P(<410) = 0.01 can only be to the left of the mean... you needed to use -2.3263.. which gave 417...
17. (Original post by Gotzz)
For part c, I used the negative z value. Because I thought it didn't make sense for the probability of X<410 to be only 0.01 if the mean is 403.
So the value I got was around 417.
I used the negative z value as well. Can't remember exactly the answer though...lemme quickly check.
18. (Original post by steviep14)
So.... last question

"each bag"... I went with that meaning "all"... but I didn't know?
I get what people mean by the last question haivng to be to the power of 10 for 4 marks, however the questions states 'weight of the cement in EACH of the 10 [email protected] surely the word each would mean that you would just use normal distribution?
19. (Original post by Son234)
Here's my exact answers to question 2

I think they are all right but correct me if I'm wrong

This was posted from The Student Room's iPhone/iPad App
Meh can't remember what I did but probably lost all the marks for b and c
20. Unofficial mark scheme anywhere for this?

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