Q9 Probability (1 Viewer)

charlesdinio

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Timothy.Siu said:
maybe if they can read it
haha yeah i made it damn obvious.

i just figured that

15/100 x 15/100 was too easy at Q9, even for 2 marks.
 

Timothy.Siu

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charlesdinio said:
haha yeah i made it damn obvious.

i just figured that

15/100 x 15/100 was too easy at Q9, even for 2 marks.
thats wat i thought,
Q9...and 2 marks...hmm
i was just suspicious
 
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If you wrote 9/400 would u get full marks or did u have to write 2.25%?
 

18836165

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Timothy.Siu said:
nah, but when u pick one, and he doesn't have a phone, then the next one you pick will have a lesser chance of having a phone.
e.g.

say there are 100,000 australian students
15% dont hav a phone so 15,000
picking 2 that dont hav a phone is 0.15x14999/99999=0.0024987....
there shouldn't be replacement
Stop over analysing the question. You obviously don't factor in the reduction of n(s) [ the sample space ] for 2 main reasons:

-It is negligible
-The question doesn't indicate how many people are in australia so you have no way of determine by what percent the sample space is decreasing by.
 

lyounamu

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adnan91 said:
So that was a question 9 and worth 2marks. Argh shud have done 2unit instead
lol

This paper was so lol-worthy that we are going to have a large influx of 120s if not 119s. So you 4 unit people wouldn't have got much out of it anyway....
 

adnan91

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lyounamu said:
lol

This paper was so lol-worthy that we are going to have a large influx of 120s if not 119s. So you 4 unit people wouldn't have got much out of it anyway....
Mental satisfaction?
 

lyounamu

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adnan91 said:
Mental satisfaction?
Yeah. And even if you get good exam done, in such an easy exam like this, your result won't be like 99 or 98 unless you get 119/120 or 120 where you can still make some silly errors - think about how you would feel if you made a silly error in 2 unit!

You would have probably wanted harder 2 unit maths...
 

adnan91

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lyounamu said:
Yeah. And even if you get good exam done, in such an easy exam like this, your result won't be like 99 or 98 unless you get 119/120 or 120 where you can still make some silly errors - think about how you would feel if you made a silly error in 2 unit!

You would have probably wanted harder 2 unit maths...
But you have an hour to check over. But anyways 4u was ok s'all gd
 

:::a:::

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Kelly47 said:
This is the kind of question we get in general, and I believe this person is right. Say there were 100 people. The answer would be 15/100 x (I think) 14/99, and then whatever that equals lol. Honestly it sounds like a general question. o_O
INVALID POST

TRY AGAIN
 

lyounamu

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erm said:
ur an idiot.

The sample space is so large that the events are considered independent NOT dependent. i.e. the probability of each event will not be affected by a previous outcome.

(as you have shown us the difference is quite small anyway)[/quote

Agreed.
 

St. Eve

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how can it be 15%x2? that would mean the probability of 2/2 not owning a phone would be greater than 1/1. it is 15%x15% which is 0.0225 or 9/400
 

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