A) Investigating Probabilities of X < 1

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1) (1 pt) You are investigating a random phenomenon and have determined that the cumulative distribution function F_{X}(x):=P(X<x) of the random variable X has values F_{X}(1)=.5, F_{X}(2)=.74, F_{X}(3)=.92

A) Less than 1 _____

B) Larger than 2 _____

C) Between 1 and 3 _____



2) Equations: None that I know of that pertain to this particular problem.


3) Part A:
0.5+0.74+0.92=2.16

So... 0.5/2.16=0.23148 Or 23.148%

I tried this for each part. I'm looking through my notes but they only have probability questions with equations.
 
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mah062 said:
1) (1 pt) You are investigating a random phenomenon and have determined that the cumulative distribution function F_{X}(x):=P(X<x) of the random variable X has values F_{X}(1)=.5, F_{X}(2)=.74, F_{X}(3)=.92

A) Less than 1 _____

B) Larger than 2 _____

C) Between 1 and 3 _____
2) Equations: None that I know of that pertain to this particular problem. 3) Part A:
0.5+0.74+0.92=2.16

So... 0.5/2.16=0.23148 Or 23.148%

I tried this for each part. I'm looking through my notes but they only have probability questions with equations.

You're given the cumulative distribution function (CDF). That gives the probability that X will be LESS than a given value x.

So what does F_X(1) signify? The answer to part a) is immediate.

Can you now figure out the other two parts?
 
Solved. Thank you!
 
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