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Problem: Given an integer $x\in\left[\text{min},\text{max}\right]$

A user comes and choose a number $\left\{ n \in \mathbb{R} : \text{min}\leq\ n \leq \text{max}\right\}$. Calculate the probability that $n > x$. I tried using following

$$\frac{\text{max}-x}{\text{max}-\text{min}}$$

But I am not getting correct answer. My book tells me that when $\text{min}=8156$, $\text{max}=15225$ and $x=12910$, then $P(n\gt x)=0.22474$, but this is not the answer I am getting.

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    Is the distribution uniform, i.e., every number has an equal probability of getting chosen? If yes, then your answer is correct. Otherwise you need to specify the distribution.2012-07-14
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    1. What does b/w mean? 2. How do you know you are not getting the correct answer?2012-07-14
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    @GerryMyerson : I would expect b/w to mean between.2012-07-14
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    @GerryMyerson According to answer book when min=8156 , max=15255 and x =12910 answer should 0.22474. But my answer is not matching with that.2012-07-14
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    @GerryMyerson update b/w = between2012-07-14
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    @Vivek: If the distribution is uniform, that answer ($0.22474$) is wrong; the correct answer is about $0.33$.2012-07-14
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    If you have stated the problem accurately, and if the distribution is assumed uniform, then the answer book is wrong.2012-07-14
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    @AndréNicolas: I think we have the real numbers here and not integers2012-07-14
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    @Thomas: Thanks, got fooled by the $n$.2012-07-14

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