Probability of being in an interval for a continuous uniform distribution

CFA Level I Quant
#1

Hey guys,
I don’t quite agree with the response since they’re giving an interval where 1<X<26, X can’t take the value of neither 1 or 26, but can only take the values in between (since there is no equal sign in 1<X<26) : [2, 3, 4, …,24, 25]. So the interval in the denominator should be 26 - 2, and not 26 - 1.

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I have the same rationale for the numerator. I think we should’ve used 15 - 6, to take all the occurences in between 15 and 1.

So the exact response is rather 9/24 = 0,37

Can someone please help?

#2

Since the distribution is continuous, think of the interval as including 1.000000000000001 and 25.9999999999999. You might be treating it like a discrete uniform by excluding 1 and 26

The standard notation used for the interval of a continuous uniform is a < x < b.

ETA: I didn’t think before I typed…

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#3

@breadmaker Man thanks for the distinction between a discrete and a continuous distribution! Completely disregarded that!

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#4

This appears to be discrete.

The thread title reads, in part, “continuous”.

(Note: I didn’t notice the other replies. Consider this an “I agree.”)

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