Each of these numerical groups conclude with the exact same number. Your mission, should you choose to accept it, is to identify the concluding number and explain why it’s the same in each case.
17, 9, ?
1, 3, 5, ?
20, 6, 3, 5, ?
HERE is the answer.
Comments (5)
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8
17-9=8
(1×3)+5=8
(20×6)/(3×5)=8
hoohooray!
posted by Grant on 9-15-2008 at 9:33 am
4!
Each is the number of letters in the spelled-out version of the previous number.
Got one!
posted by Betsy on 9-15-2008 at 10:32 am
I liked Grant’s answer better than the actual one.
Good job Grant!
posted by Ryan on 9-15-2008 at 11:28 am
I figured out 4 for myself, as Betsy did.
However, you could work out a polynomial equation for each sequence, and prove that the next number is anything you want it to be. I prefer 42, myself.
posted by PuzzleScott on 9-15-2008 at 1:40 pm
I came up with the same answer as Grant except my final line looks like this:
((20*6)/3)/5 = 8
It never even occurred to me to think of it as a letter puzzle.
posted by Howlin' Hobbit on 9-15-2008 at 5:54 pm