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# Consider the following sequence: 2, 22, 222, 2222, 22222 etc

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Re: Consider the following sequence: 2, 22, 222, 2222, 22222 etc [#permalink]
First I tried to solve using sequence but it is lot easier to simply calculate units and tens digits as is.
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Re: Consider the following sequence: 2, 22, 222, 2222, 22222 etc [#permalink]
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There are 50 2s in the unit place and 49 2s in the tens place. The unit digit is 0 and carry over will be 10. For tens digit 98 and carry 10 will add up to 108. Thus, ten's digit will be 8.
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Re: Consider the following sequence: 2, 22, 222, 2222, 22222 etc [#permalink]
I worked it this way, can anyone check the method please?

Sum of 1: 2 is in 10th digit
Sum of 2: 2 is in 10th digit
Sum of 3: 4 is in 10th digit
Sum of 4: 6 is in 10th digit
Sum of 5: 8 is in 10th digit
Sum of 6: 0 is in 10th digit.

Then the pattern continues 2-4-6-8-0, and therefore the 50th will be same as the 5th, as the sequence is by 5 terms.
So 50th is 8.

Is this pattern correct? Or I was lucky to get it?
Re: Consider the following sequence: 2, 22, 222, 2222, 22222 etc [#permalink]
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