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Stat v. 62

Messages
41
Reaction score
14
Points
18
we can discuss all the answers? i remember many of them would like to know if they are correct
 
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pretty much.
I did the back calculations.
the z value for c was 1.881, which gave a probability of .97
1.881- (1-1.881) = .97 - 1 + .97
total probability = .94 or 94%
Oops i took z value as -1.881 thats y my answer is wrong :/
well that reduces my total to 43 :(
 
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can you write down the process for calculation of the value of c
still cannot figure out y i lost marks in that part
P(445-c<X<445+c)=0.94(i think mean was 445 and s.d was 3.6 or 3.61 i think)
P(445-c-445/3.61<Z<445+c-445/r)=.94
P(-c/3.61<Z<c/3.61)=.94
2P(Z<C/3.61)-1=.94
P(Z<C/3.61)=(1+.94)/2
P(Z<C/3.61)=.97
c/3.61=1.881
so c=6.79
 
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if i only did till here
P(445-c<X<445+c)=0.94(i think mean was 445 and s.d was 3.6 or 3.61 i think)
P(445-c-445/3.61<Z<445+c-445/r)=.94
P(-c/3.61<Z<c/3.61)=.94
2P(Z<C/3.61)-1=.94
do you think i wil get half the mark
 
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can you write down the process for calculation of the value of c
still cannot figure out y i lost marks in that part


P <(445+c)
P >(445-c)
(445+c -445/3.6) - (445-c-445/3.6)
= c/3.6 - (-c/3.6)
Let the probability for c/3.6 be 'x', then the probability for -c/3.6 is '-x'
so x- (-x) = .94
x- 1 + x =.94
x = .97
z value for .97 is 1.881
So, c/3.6 =1.881
c= 6.77
 
Messages
41
Reaction score
14
Points
18
if i only did till here
P(445-c<X<445+c)=0.94(i think mean was 445 and s.d was 3.6 or 3.61 i think)
P(445-c-445/3.61<Z<445+c-445/r)=.94
P(-c/3.61<Z<c/3.61)=.94
2P(Z<C/3.61)-1=.94
do you think i wil get half the mark
i think they will cut 2 marks if you did till that but not sure though. I am not very familiar with their marking.
 
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