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I can't seem to understand the question - how can a digit + 5 = 4? Are we talking about rounding numbers here?

Can someone please explain?

Hi, It's been asked about tens digit of K+5=4 hence its possible to have 4 as answer.... Answer should be B. My explanation for the answer as follows; 1. K>35 Stmt one satisfies many numbers starting from 36 till 44 where tens digit of k+5 is 4 (E.g. 36+5=41, 37+5=42....41+5=46). Here tens digit of K has two options either 3 or 4 hence can't answer uniqure number K.

2. Unit Digit of K is >5 For this we have only 4 options available which satisfies tens digit of k+5=4 condition. Numbers are 36, 37, 38 and 39. All these 4 numbers have only one unique number as tens digit i.e. 3 Hence we got our answer. Hence B is suff to answer the question.

Question stem says 40 <= k+5 <= 49, thus 35 <= k <= 44 Statement 1 says k > 35, thus 36 <= k <= 44. Tens digit could be 3 or 4, insufficient Taking into account the range of k provided in the question stem, statement 2 says that 36 <= k <= 39. Units digit must be 3, sufficient Answer B

I can't seem to understand the question - how can a digit + 5 = 4? Are we talking about rounding numbers here?

Can someone please explain?

I solved it this way:

Stmt1:

Now the possible values satisfying this statement and question statement are: where, nos in bold represtents K.

36+5=41 37+5=42 38+5=43 ' ' ' till 44+5=49

But since there are are two answers for ten's Digit of K ie 3 and 4, stmt 1 is NS.

Now taking stmt2 alone we can say that all the values where K's Ten's digits is 3 qualifies the statement condition, hence it is sufficient alone.All other values with K's Ten's digits as 4 will not qualify because in that case the 2nd stmt condition that K's unit digit is greater than 5 is not met.

If k is a positive integer and the tens digit of k+5 is 4, what is the tens digit of k?

Translate the stem: "the tens digit of k+5 is 4" --> 40\leq{k+5}\leq{49} --> 35\leq{k}\leq{44} --> so the tens digit of k could be 3 or 4.

Side note: strictly speaking k could be more than two digit number (for example 3-digit x40\leq{k+5}\leq{x49} ), though as we are interested only in units and tens digit then this wouldn't change anything and we can neglect other digits.

(1) k > 35 --> just tells us that k\neq{35}, so we have 35<{k}\leq{44} --> the tens digit of k could still be 3 or 4. Not sufficient.

(2) The units digit of k is greater than 5 --> k could only be 36, 37, 38, 39 --> so the tens digit of k is 3. Sufficient.

I can't seem to understand the question - how can a digit + 5 = 4? Are we talking about rounding numbers here?

Can someone please explain?

Hi, It's been asked about tens digit of K+5=4 hence its possible to have 4 as answer.... Answer should be B. My explanation for the answer as follows; 1. K>35 Stmt one satisfies many numbers starting from 36 till 44 where tens digit of k+5 is 4 (E.g. 36+5=41, 37+5=42....41+5=46). Here tens digit of K has two options either 3 or 4 hence can't answer uniqure number K.

2. Unit Digit of K is >5 For this we have only 4 options available which satisfies tens digit of k+5=4 condition. Numbers are 36, 37, 38 and 39. All these 4 numbers have only one unique number as tens digit i.e. 3 Hence we got our answer. Hence B is suff to answer the question.

If you like explanation, consider for kudos....

I agree. The way the question is worded is misleading. Initially even I took it to be the tens digit of a number + 5 = 4 i.e. if a two digit number was say TU then T+5 =4. It made no sense. So I decided that it was one of those badly worded questions and took it to be k + 5 instead of T + 5. Once I got that correct, the question seemed pretty straight forward from there on... The trap here is that the question doesn't ask for the number k, rather asks what is the tens digit i.e. T. Thus B is sufficient. _________________

-DK --------------------------------------------------------- If you like what you read then give a Kudos! Diagnostic Test: 620 The past is a guidepost, not a hitching post. ---------------------------------------------------------