Madelaine88 wrote:

If n is a positive integer, what`s the tens digit of n?

1) The hundreds digit of 10n is 6

2) The tens digit of n + 1 is 7

1) 10n will just add a 0 to the units place and shift every digit by 1 to the left; that's all.

If Hundred's place of 10n = 6; Ten's place of n must be 6

Sufficient.

2)

If n=69; n+1=70;

If n=73; n+1=74;

So; ten's place of n+1 is 7 for both the values discussed above.

Thus; ten's place of n may be 6 or 7.

Not sufficient.

Ans: "A"

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~fluke

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