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How many times does the digit 9 appear in the list of all integers from 1 to 600?

 Oct 24, 2020
 #1
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From 1 to 9          = 1 time
From 10 to 99      =19 times
From 100 to 600  =20 x 5 =100 times
1 + 19 + 100 =120 times between 1 and 600
Note: This counts repeated 9's such as 99, 199....etc.

 Oct 24, 2020
 #2
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Hint:

 

From 1-89 - nine "9"s

From 90-99 - eleven "9"s

 

Try using this for the three digit numbers smiley

 Oct 24, 2020

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