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Edexcel S1 A Level Maths

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Does anyone have any notations on probability?

i.e: P(A|B) = P(AnB) divided by P(B)
Original post by dgammaldi10
Does anyone have any notations on probability?

i.e: P(A|B) = P(AnB) divided by P(B)


Hi, what do you mean? :colondollar:
Can someone please help me with this question?
'1. There are 16 competitors in a table-tennis competition, 5 of which come from Racknor
Comprehensive School. Prizes are awarded to the competitors finishing in each of first,
second and third place.
Assuming that all the competitors have an equal chance of success, find the probability that
the students from Racknor Comprehensive
(a) win no prizes, (3 marks)
Original post by Fas
it tells you that 40% don't read newspapers at all - so the union is everybody that reads A newspaper of some description ( in this case quality or tabloid as they are the only two newspapers given ) hence 1 - 0.40 = 0.60 which is the union :smile:


Eureka!!! Thank you so much, maths genius! You've saved my Maths life :tongue:
I'm still feeling a little hopeless for this exam :frown: hope I'm not the only one!!


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Reply 384
can someone please post or PM the jan 2013 S1 paper ? Really want to have a go at it before the exam tomorrow :L
Reply 385
Original post by yl95
Can someone please help me with this question?
'1. There are 16 competitors in a table-tennis competition, 5 of which come from Racknor
Comprehensive School. Prizes are awarded to the competitors finishing in each of first,
second and third place.
Assuming that all the competitors have an equal chance of success, find the probability that
the students from Racknor Comprehensive
(a) win no prizes, (3 marks)


Probability that a competitor isn't from Racknor Comprehensive is 11/16. This would apply for the first prize. Therefore, second prize is 10/15 and third is 9/14. Once someone has won first prize, they're out of the competition, so we can take out 1 from the total. The same applies to the third prize. You could also draw a tree diagram for this to help you visualize it.

Then we do 11/16 * 10/15 * 9/14 = 0.295
Reply 386
Original post by yl95
Can someone please help me with this question?
'1. There are 16 competitors in a table-tennis competition, 5 of which come from Racknor
Comprehensive School. Prizes are awarded to the competitors finishing in each of first,
second and third place.
Assuming that all the competitors have an equal chance of success, find the probability that
the students from Racknor Comprehensive
(a) win no prizes, (3 marks)


Solomon paper I did that one aha
It's basically
11/16 x 10/15 x 9/14

Racknor is 5 so the rest 11
Ad it's saying basically that those 11 win each game

I think that's right??


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Reply 387
Original post by iAhmedd
can someone please post or PM the jan 2013 S1 paper ? Really want to have a go at it before the exam tomorrow :L

paper and mark scheme here: http://www.thestudentroom.co.uk/showpost.php?p=42644309&postcount=307
Reply 388
Ugh the Jan 2013 paper was a killer, I'm hoping to do better in my resit tomorrow :frown: Good luck guys!


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Good luck to everyone tomorrow :smile: Hope the paper is nice and easy :wink:
(edited 10 years ago)
Original post by Air1337
Probability that a competitor isn't from Racknor Comprehensive is 11/16. This would apply for the first prize. Therefore, second prize is 10/15 and third is 9/14. Once someone has won first prize, they're out of the competition, so we can take out 1 from the total. The same applies to the third prize. You could also draw a tree diagram for this to help you visualize it.

Then we do 11/16 * 10/15 * 9/14 = 0.295

Thank you! Just drew a tree diagram and it all seems clear to me now.
Ok guys, when drawing the regression line do you only plot the means or do you have to plot anything else?
Reply 392
Would the P(B') be 1 - P(B)?
Original post by GSB
Would the P(B') be 1 - P(B)?


Yep. :yep:
Original post by GSB
Would the P(B') be 1 - P(B)?


Yes
Reply 395
Just to clarify is this correct?

3e3397a014ada259c99998918bed6c1d.png
is the type of probability distribution we are going to be looking at always Discrete Uniform distribution?
can someone please help me understand 5a on june 2006, I just don't get how they got that diagram!
Reply 398
Original post by Secret.
Just to clarify is this correct?

3e3397a014ada259c99998918bed6c1d.png


Nope, it would be everything outside the circles + what you shaded + intersection.
list of definitions etc we may be asked to know?

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