Stats help needed!

[usman.1995]

I am facing in solving 2 Qs from past papers
Q1
paper 12 ....oct nov 2010 ....Q5.(i).(c)...unable to understand hoe 34 answer comes as mentioned in the examiner report of this paper

Q2
paper 13.....oct nov 2010.....Q6 (ii).....don't know how to prove it

Someone plz explain ......THANKS

 

[abcde]

I don't have the examiner report for this year but I do get 34 as the answer to your first question. The second statement "There were no pupils for whom the predicted grade and the grade obtained were more than one grade apart" tells you that for candidates who had D as their predicted grade actually got two different grades only: C and D. If one-third of them got C, then students who got C= 1/2 x 68 = 34. 34 is one-third of the total (34+68= 102).