on a scale from 1 to 10

i've got an HILARIOUS joke that i play when someone asks me to rank something on a scale from 1 to 10. it goes like this:

them: on a scale of 1 to 10, how [whatever it is]
me: is one or ten high?
them: ten.
me: five.

see how hilarious that is? my answer is the same regardless of the orientation of the scale. HILARIOUS!

except: the middle of 1 and 10 is 5.5, not 5. but that's not as funny. not nearly as funny. am i indeed better served by making the arithmetically inaccurate but funnier answer, or should i strive for accuracy in joke-making?