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Suelyn counts up from 1 to 9, and then immediately counts down again to 1, and then back up to 9, and so on, alternately counting up and down. 

 

Ex. (1,2,3,4,5,6,7,8,9,8,7,6,5,4,3,2,1,2,3,4,5,6,7,8,9,8,7,6,5,4,3,2,1...)

 

What is the 1000th integer on her list?

 

Attempts so far: 

 

Okay. So I tried dividing 1000 by 9-which got me 111R1, then I remembered it's not like, "1,2,3,4,5,6,7,8,9,9,8,7,6,5,4,3,2,1..." But rather, "1,2,3,4,5,6,7,8,9,8,7,6,5,4,3,2,1..."

I accidentally added another nine... Is there any way to remove it?

 Aug 16, 2020
 #1
avatar+118587 
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Ex. (1,2,3,4,5,6,7,8,9,8,7,6,5,4,3,2, this is where the pattern restarts   1,2,3,4,5,6,7,8,9,8,7,6,5,4,3,2,      1...)

 

So there are 16 numbers before the pattern repeats.

 

so it will be  1000 mod 16

 

1000/16=62.5 = 62 remainder 8

the 8th number in the pattern is 8

 

so the 1000th digit is 8

 Aug 16, 2020

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