# Another Die question

#### ITman95

##### New Member
If one was to roll a fair day and if the outcome is 2 then select a number at random in [1,2] and other wise select a number at random in [2,3]. if the number selected is X then find the PDF Fx of X.

im a bit confused on how to answer this, any input would be appreciated.

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#### asterisk

##### New Member
Are you sure you have the right ranges here? In both cases you are selecting a number from the same range.

#### ITman95

##### New Member
OOPS!! thanks for pointing that out, fixed my original post with the correct ranges.

#### BGM

##### TS Contributor
1) Do you know how to calculate and specify CDF for a continuous uniform random variable?

2) Have you heard about the mixture distribution?

#### ITman95

##### New Member
i dont know about mixture distribution BUT how can you apply CDF for this ?

#### ITman95

##### New Member
i just used PDF to get my answer but not sure if it is correct.

PDF of x is Pr(x=k)=1/6 for k=1,2,3,4,5,6

so CDF would be
Pr(x<=1)=1/6
Pr(X ≤ 2) = 2/6

and so on...

is this the correct way to solve this or am i doing something wrong ?

#### BGM

##### TS Contributor
Now you are calculating the CDF at some points for a discrete uniform distribution.

You need to first know to calculate and specify the CDF at any point for a continuous uniform distribution.

#### ITman95

##### New Member
yes because when it reaches 1 it becomes constant because it cannot be greater than 1