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# Normal Distribution Help Watch

1. I'm stuck on this question for normal distribution, if anyone can help me that would be great.

If X is a normally distributed variable with a mean of 24 and standard deviation of 2. Find:

(a) p(X>28 | X ≥ 26)

(b) p(26 < X < 28 | X ≥ 27)

thank you so much!
2. (Original post by need_math)
I'm stuck on this question for normal distribution, if anyone can help me that would be great.

If X is a normally distributed variable with a mean of 24 and standard deviation of 2. Find:

(a) p(X>28 | X ≥ 26)

(b) p(26 < X < 28 | X ≥ 27)

thank you so much!
Ok
Do you know how to convert to the standard normal? X to Z?
Do you know the P(A|B) from the probability section? (A given B)
3. (Original post by m4ths/maths247)
Ok
Do you know how to convert to the standard normal? X to Z?
Do you know the P(A|B) from the probability section? (A given B)
I know how to do those 2 things but I don't know how to use it in this question
4. (Original post by need_math)
I know how to do those 2 things but I don't know how to use it in this question
OK find the P(X>28), write it down.
find P(X>26), write it down.

We can go from there.
5. (Original post by m4ths/maths247)
OK find the P(X>28), write it down.
find P(X>26), write it down.

We can go from there.
p(X>28) = 0.0228

P(X>26) = 0.1587
6. (Original post by need_math)
p(X>28) = 0.0228

P(X>26) = 0.1587
Ok, now apply P(A|B)
(This one just requires a bit of common sense)

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