The robot Lumber9 moves along the number line. Lumber9 starts at 0, takes 1 step forward (to 1), then 2 steps backward (to -1), then 3 steps forward, 4 steps backward, and so on, moving alternately forwards and backwards, one more step each time.
At what number is Lumber9 after 2011 steps?
Select one option, then click Submit.
1006
27
11
0
-18
Select an option, then submit.
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