Edexcel S2 - 27th June 2016 AM

Its basically sum of fx /divided my the sum of f

and for variance its E(X^2)- (E(X))2. meaniing the sum of fx^2 insead.

That sounds confusing lol but its usually in s1 but they put it on s2.

Hope that helps!!

Question 1a) U = 1.44 Var(x) = 1.44 (3 Marks)b) U was approximately Variance (1 Mark)c) I – 0.251 II – 0.777 (4 Marks)d) 0.1378 (3 Marks)e) 0.152 (3 Marks) (Might be 0.132 – Rushed this onmy copy of answers) Question 2a) N=60 (2 Marks)b) I – 0.0133 II -0.0159 (5 Marks)c) 0.2396>0.01 Keep H0 (5 Marks)Question 3a) f(x) = ¼ 5=<R=<9 , 0 otherwise (1 Marks)b) 0.5 (1 Marks)c) 158.13 (4 Marks)Question 4a) Show that (6 Marks)b) K = 1/9 (4 Marks)Question 5 N = 225(I applied continuity correction – I honestly didn’t know if I should) (8Marks)Question 6a) 9 samples (2 Marks)b) 4 = ¼ , 5 = 3/10 , 6= 29/100 , 7 = 3/25, 8 =1/25 (5 Marks)c) N=57 (3 Marks)Question 7a) 1.2 (4 Marks)b) 0.24 (4 Marks)c) 0.325 (3 Marks)d) £41.88 (2 Marks)e) Shouldn’t remove staples (2 Marks) I’m not claiming these are all right – let me know J These are what I wrote

I agree with all of these, except n=57 on question 6

oh my god - is this from S1 lol.. seems I completely forgot how to do this !!! oops ... will I get a mark for using the variance formula even though my E(X) and E(X^2) were wrong . dammit edexcel asking S1 in S2 !!!

What was Q3 about?

Q3b) is not 0.75, 10 is outside the boundary so 7<X<9 is 0.5

Can someone please explain E(A), as i got it to equal 49pi.

E(R) = (9+5)/2
E(R) = 7

E(A) = pi * 7^2
E(A) = 49pi

Can someone please explain E(A), as i got it to equal 49pi.

E(R) = (9+5)/2
E(R) = 7

E(A) = pi * 7^2
E(A) = 49pi

Can someone please explain E(A), as i got it to equal 49pi.

E(R) = (9+5)/2
E(R) = 7

E(A) = pi * 7^2
E(A) = 49pi

Question 1a) U = 1.44 Var(x) = 1.44 (3 Marks)b) U was approximately Variance (1 Mark)c) I – 0.251 II – 0.777 (4 Marks)d) 0.1378 (3 Marks)e) 0.152 (3 Marks) (Might be 0.132 – Rushed this onmy copy of answers) Question 2a) N=60 (2 Marks)b) I – 0.0133 II -0.0159 (5 Marks)c) 0.2396>0.01 Keep H0 (5 Marks)Question 3a) f(x) = ¼ 5=<R=<9 , 0 otherwise (1 Marks)b) 0.5 (1 Marks)c) 158.13 (4 Marks)Question 4a) Show that (6 Marks)b) K = 1/9 (4 Marks)Question 5 N = 225(I applied continuity correction – I honestly didn’t know if I should) (8Marks)Question 6a) 9 samples (2 Marks)b) 4 = ¼ , 5 = 3/10 , 6= 29/100 , 7 = 3/25, 8 =1/25 (5 Marks)c) N=57 (3 Marks)Question 7a) 1.2 (4 Marks)b) 0.24 (4 Marks)c) 0.325 (3 Marks)d) £41.88 (2 Marks)e) Shouldn’t remove staples (2 Marks) I’m not claiming these are all right – let me know J These are what I wrote

grade boundary predictions? I got somewhere between 62-70 and need 80UMS in this exam