[jamesbressi]

What does it mean when you can't answer the question properly and said "4.5"?

[sukuriant]

You're either a math major or an engineer. We can't do simple math anymore. Please give it to us in the form of an integral.

Also, there's the ambiguity of "inclusive or exclusive? And, which side?"

[1,9], (1,9], [1,9) or (1,9)?

[kylebrown]

Those ambiguities make no difference to the answer. Answering 4.5 just means you forgot that starting a count from 0 gives a different total than starting from 1.

[nostromo]

4.5 is halfway between 0 and 9. Halfway between 1 and 9 is 1+(9-1)/2 = 5

[JoeAltmaier]

Nu-uh. By that math, halfway between 1 and 2 is.... 1?!