Andrew finds that on his way to work his wait time for the bus has a roughly uniform distribution between 10 minutes and 17 minutes. One day he writes down his wait time rounding down to the half minute.

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What is the probability that Andrew waits for 12.5 minutes?

$\displaystyle {P}{\left({X}={12.5}\right)}=$ Preview Question 6 Part 1 of 4   .

What is the probability that Andrew waits between 10.5 and 12.5 minutes?

$\displaystyle {P}{\left({10.5}\le{X}\lt{12.5}\right)}=$ Preview Question 6 Part 2 of 4  

The sum of all the probabilities of X is $\displaystyle {P}{\left(-\infty\lt{X}\lt\infty\right)}={P}{\left({10}\le{X}\lt{17}\right)}=$

The area of all the bins in the bar graph is square units. So for a discrete random variable we find the CDF by taking the sum of probabilities, not area.