# Rounding Error

Probability Level 2

A number is uniformly chosen from $[0.15, 0.25]$. It was rounded to two decimal places and then to one decimal place. The probability that the final value is $0.2$ is $X \%$. What is $X?$

Assumption: Use rounding "half away from zero". That is, if the number is equally far from the two closest numbers, choose the one away from zero. For example, 2.5 is equally far from 2 and 3, so round 2.5 to 3.

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