The Student Room Group
Reply 1
yeah i did it, it wasnt too bad except i got a nose bleed to had to go out for abit lol. can you remeber what you got for anything?
Reply 2
use the other thread.
on second thoughts. it's been hijacked. :biggrin:

--------------

i remember the combinations question:
part a i got 140
part b 45/140
part c 80
Reply 3
cant remeber what i got for b, but for c i got 95 oops, i expect your right looking at your cambridge offer lol.
Reply 4
Hold on how did you get 45/140? i got 30/140!
You had to multiply the probability of gettin A1 from the first bunch with not gettin B1 from the 2nd lot
Reply 5
discuss the first two questions XD because i thot they were annoying
Reply 6
the first two questions were ok, probability of her passing = pass first time + (fail and pass 2nd time)

then the second part of question 1 you had to rearrange to find the probabilty of him passing 2nd time because you were only given probabilty of passing.

quesiton 2, s.d stayed the same, and the mean was 124.8 100 more. part b ermm was on discussing the heights which involves abit of waffling and part c was to calculate the new mean so you times 124.8 by 50 to get sum of x, and then the other mean by 100 to get the other sum of x, add them together and divide by total which was 150. i think thats right but feel free to correct me..
Reply 7
S. Tham
Hold on how did you get 45/140? i got 30/140!
You had to multiply the probability of gettin A1 from the first bunch with not gettin B1 from the 2nd lot

A1 A2 A3 A4 B1 B2 B3 B4 B5 B6 B7
He has to choose A1
therefore he has to make two choices from any of A2 A3 A4
3C2 = 3

he cant choose B1:
therefore he has to make 4 choices from B2 B3 B4 B5 B6 B7
6C4 = 15

3*15 = 45

Probability of this occuring is 45/140
Reply 8
I swear you guys did a completely different paper to me!

Just to clarify was the last question on doughnuts? I was hungry at the time it didn't help
Reply 9
Undry1
A1 A2 A3 A4 B1 B2 B3 B4 B5 B6 B7
He has to choose A1
therefore he has to make two choices from any of A2 A3 A4
3C2 = 3

he cant choose B1:
therefore he has to make 4 choices from B2 B3 B4 B5 B6 B7
6C4 = 15

3*15 = 45

Probability of this occuring is 45/140


well lol, i put the probability of chosing A1 was 1/3 as he had to choose 3 quetion from A1,A2,A3,A4. So one of the 3 questions is A1 so A1 has P=1/3...........n then Prob B1 was not picked is 3/7 as the prob it could be picked was 4/7. So my overall answer was 1/3 multiplied by 3/7 = 1/7


but i messed up this whole question, for the first part, was it 4C3*7C4, OR 4P3*7P4(I put this but think it wrong').....last part, i shud get some follow on marks here, not a good question, probably the only qhole question i got wrong in the qwhole paper , not happy :mad:

--------------

you can mock me all you want
Reply 10
i thought that was the toughest question on the paper, i know i got b and c wrong part A was combinations so 4c3 x 7c4 which was 140. how marks were given for parts b and c any1 remember?

any1 remeber the answers to any other questions?
Reply 11
I thought the paper was OK. This was my only January exam, so I went on a mission and I did all the past papers back to 2001. The questions asked year to year really don't change at all.
Reply 12
spearmans rank r=0.866666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666

product moment correlation coefficient r=0.698 summat

--------------

africa capital city, 1 million, it shud be x on y coz we get given the y value so it would be easier and more convinient as x on y gives the regression line form as x = a + by , so u get the point hopefully.
Reply 13
lol yeah i got that for the spearmans rank and pmcc. what did you get for the first question and the one about 20 trays of seeds and atleast 8 seeds in 19 trays germinated?
Reply 14
20 times (1-0.0702)^19 times 0.0702^1
Reply 15
isnt it that plus (1-0.0702)^20 because it was atleast 19. so p(x=19) + p(x=20)
Reply 16
.x.g.x.
isnt it that plus (1-0.0702)^20 because it was atleast 19. so p(x=19) + p(x=20)


it was not atleast, it was atleast 8 seeds, in 19 trays wasnt it lol
Reply 17
i thought it was at least 19 trays as well. :biggrin: