If k is a positive two-digit integer, what is the tens digit of k?

Question

If  k   is a positive two-digit integer, what is the tens digit of  k ?

1) The sum of the tens digit of  k  and the units digit of  k   is 5.

2) The tens digit of  k  + 6 is 3.

chetan2u · Accepted Answer

hi,

1) The sum of the tens digit of  k  and the units digit of  k   is 5. 
the tens digit could be 5 as in 50, 4 as in 41, 3 as in 32, 2 as in 23 and 1 as in 14..
different values possible
Insuff

2) The tens digit of  k  + 6 is 3 
if k is between 24 and 33, both inclusive, k + 6 will have 3 as tens digit..
so possible value of k is 2 and 3..

combined.. 
there are two values of k possible with tens digit as 2 and 3 - 23 and 32..
But ONLY 32 +6 will give tens digit as 3, 23 +6 = 29 and hence it has 2 as tens digit..

C

CounterSniper · Answer

you added 6 to the tens digit directly !!

The question says  K+6  
and k = say 10a+b
from statement 1 
a+b=5
possible cases
14
41
23
32
50

from statement 2
pick any of these cases and add 6 to it , this should give tens digit as 3

the only possible value , K =32
as 32 + 6 =38 where tens digit is 3

Therefore C

shriraj93 · Answer

I am bit confused here. lets assume x and y are tens, and unit digit of K. i.e k =xy

1) The sum of the tens digit of k and the units digit of k is 5.

x+y=5

not enough.
2) The tens digit of k + 6 is 3.

then according to this statement it should be x+6=3 cause x is tens digit.

but this is not possible so answer is E.

Help me to understand the second statement. I am strugling with these kind of senteses.

warriorguy · Answer

Hi, I agree with your solution - but from the question stem: it says that "The sum of the tens digit of k and the units digit of k is 5."

so shouldn't the possible cases you mentioned also include 05 ?

chetan2u · Answer

Hi,
The reason 05 is not included is that05 is same as 5 and thus is a ONE digit number, BUT we are asking about TWO digit numbers.....

If we are talking of making codes etc then 05 will be a case but not here...

warriorguy · Answer

oh my! I feel like a dumb f***. Thanks Chetan

AnkurGMAT20 · Answer

avigutman   Bunuel , could you please help me understand the second statement here?

It says that The tens digit of k + 6 is 3. Suppose K = ab, as per my understand it says a+6 = 3. I know I'm missing something here, but not able to figure it out.

avigutman · Answer

If the tens digit of k is a, and the units digit of k is b, as you suggested  AnkurGMAT20 , then the value of k is 10a + b.
In that case, k + 6 = 10a + b + 6
So I think you misinterpreted the statement. It's not saying " (the tens digit of k) + 6 is 3 ". Rather, it's saying " the tens digit of (k + 6) is 3 "

bumpbot · Answer

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If k is a positive two-digit integer, what is the tens digit of k?

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If k is a positive two-digit integer, what is the tens digit of k?

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