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Normal Distribution


How do you do 7b?
Original post by zed963

How do you do 7b?

Since 232 is the mean. You can say that P(Z>w-232/5)=0.3. This is because the whole bit is 1 so the half to the right is 0.5.
0.2 is surrounded by the mean and w, so 0.3 is what is left which is the area to the right. Work this out by using the percentage points table then solve for w. If that makes sense :tongue:
Reply 2
Original post by Super199
Since 232 is the mean. You can say that P(Z>w-232/5)=0.3. This is because the whole bit is 1 so the half to the right is 0.5.
0.2 is surrounded by the mean and w, so 0.3 is what is left which is the area to the right. Work this out by using the percentage points table then solve for w. If that makes sense :tongue:


w=234.62

then how would you do part c?
Reply 4


You've done something wrong there I'm certain.
Original post by zed963
w=234.62

then how would you do part c?

mm not sure.
Original post by zed963
You've done something wrong there I'm certain.


yeah I have. Really shouldn't be working this late :tongue:
Original post by zed963
w=234.62

then how would you do part c?


use a tree diagram

you know the probability of getting (W<232<w) is 0.2 so the probability of not getting that is 0.8 then do jar 1 then jar 2 then collect all the possible probabilities

exam solutions has a good video on this question
Reply 8
Original post by studentwiz
use a tree diagram

you know the probability of getting (W<232<w) is 0.2 so the probability of not getting that is 0.8 then do jar 1 then jar 2 then collect all the possible probabilities

exam solutions has a good video on this question


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