how ws math xams guys paper 62 ??!!

[darenchamp08]

if u understood the question correctly it was something like that:
'given that 5 drama students were choosen, find the probability that atleast one of them is a boy'
thats why i choose CP

 

[DonOmarCorleone]

well if u check June 2007 paper question 6 part (i)

u will see that it was pretty similar to ours and u didn't have to use CP there, just binomial distribution. i don't know maybe i got mixed up but those two questions looks exactly like each other and there was no given in both.

 

[1357913579]

dranemchamp08 please can you tell me me the probability of xmore thaen1 given in the question plese

 

[1357913579]

or anyone pleaaseeee tell me that probability iam scared

 

[djdead1]

so u pretty much did a tree diagram and conditional probability i don't know why u ppl chose that! there was no sign like in all the previous papers to use the CP formula

exactly. they just said what is the probability of atleast one of them being a boy

 

[darenchamp08]

dranemchamp08 please can you tell me me the probability of xmore thaen1 given in the question plese

P(X>1) i got answer MU=1.54

 

[DonOmarCorleone]

lol ok didead1, can u please take a look at June 2007 paper, question 6 part (i) and tell me what u think

 

[DonOmarCorleone]

yo didead1, are u agreeing with my point of view or ur with the others by saying exactly? lol kind of confused here sorry XD

 

[djdead1]

yo didead1, are u agreeing with my point of view or ur with the others by saying exactly? lol kind of confused here sorry XD

All im saying is im doomed if it was CP :/

 

[1357913579]

oh my god no one is understanding me see the question was x is normally distributed with mean, 2 mean which is sd then it was wriiten the probability of x is more then 1 = to something it was wriiten in the question so please i need that probability so i can solve and check how i did and compre with your answer pleaseeee and at the end did you got 3mean = to something and then divide that value by 3 and get the mean pleaseeeeeeeee tell me iam pissed

 

[DonOmarCorleone]

oh man thank god there is someone else who thinks it was not CP lol! was starting to lose hope for real XD

anyway do u still remember ur answer?

 

[DonOmarCorleone]

i'm really sorry bro i can't really help u cause i don't remember exactly what was written in the question :S don't wanna give u random info and after that u will get scared and might scare all of us in turn XD

 

[1357913579]

se honestly iam sure we can use the codition probability maybe youre method is also correct as i have seen that there are lots of methods for one question so thats the thing but still i wanted to sk atleast you remember at the end you got something like 3mean = something then divide by 3 to get mean=something

 

[AlphaCentauri]

Didn't use CP. My ans was 0.701. Not sure though.

 

[DonOmarCorleone]

oh nice but i got something like 0.710 though XD i don't know auragirl! this question has been solved by 10 ways till now i guess XDDDDDDDDDDDDD

what do u think of the way i solved it though it's on page 4, please check it out and tell me how much u think i might lose! not looking for A* or anything, i just need an A and am worried like hell lol

Ur help will be greatly appreciated thanks in advance.

 

[AlphaCentauri]

I don't correct papers, so only CIE will give you the marks. I cannot speculate for them, sorry. I hope you understand. If I give you false hopes, you will kill me telepathically. If I crush the little hope you have, you are still going to kill me.

I got it as 0.701.

We talk about it when the rest of the papers are over? I'll explain to you then.
Best wishes for others.

 

[AlphaCentauri]

Here's what I did for question 6.

Boys doing Drama: 10%*60% = 0.06
Girls doing Drama: 55%*40% = 0.22

P (Boy does drama) = 0.06/ (0.06+0.22)
= 3/14

Yes, I realised this is actually CP itself. Just in the exams, I used my logic to attempt the question, preferring not to explicitly use CP and take a risk since I wasn't sure.

Then, X ~ B (5, 3/14)

P ( X greater or =1)= 1- P (X=0)
= 1- (11/14)^5
= 0.701 (to 3 sig.fig.)

Apologies for the late reply. I had to prepare for my papers.

 

[markskoop]

guys.....wht do u think would b the threshold for stat????