Data Sufficiency

A,B and C are 3 digit integers, where A = B + C. Is the hundreds' digit of number A equal to sum of hundreds' digit of B and C ?
1) Tens' digit of A = Tens' digit of B + Tens' digit of C
2) Units' digit of A = Units' digit of B + Units' digit of C

OA = After some discussion.

Should be A.

Stmt 1

a = b + c.

(1)) Tens' digit of A = Tens' digit of B + Tens' digit of C
this means that sum of tens digit of b and tens digit of c should be less than 10.Interestingly, this also forces that sum of unit digits should be less than 10.
That being the case, the hunderedth digit of a will always be equal to hundered digits of b and c
do few ex.

b = 235, c= 543 a = 778

b = 587, c = 332, a = 919 - sum of tens digit of b and tens digit of c not less than 10.

b = 154, c = 255 a= 409 - sum of tens digit of b and tens digit of c not less than 10.

sueff,


Stmt 2
not sueff

try different combinations.

b= 103, c = 203 a = 306. works

b= 153, c = 253 a = 406. does not work

Here OA = E....

I am not sure how....

can someone please tell how E is correct ?

goelmohit2002 wrote:Here OA = E....

I am not sure how....

can someone please tell how E is correct ?

I guess OA is wrong.

Thanks,
Quant-Master

am getting A as well.
what is the source?

Thanks all. I too was puzzled by the OA...

I guess the correct answer should be A.

scoobydooby wrote:am getting A as well.
what is the source?

One of my friends who is studying in a reputed GMAT coaching institute gave me this question.....his class assignment had this question.

I have not thought about it enough

but it may be because the numbers can be negative

numbers?

woo wrote:I have not thought about it enough

but it may be because the numbers can be negative

numbers?

Thanks woo....good point !!!

Can you please illustrate how does -ve numbers will impact the answer ?

IMO E


Stmt 1:

Tens' digit of A = Tens' digit of B + Tens' digit of C

Insufficient - This does not talk about the hundreth digit

Case 1:

B = 123, C = 321, A = 444

123 + 321 = 444 ------> This eqn satisfies the stmt 1 and also, from this we can conclude that the hundreth digit of A is equal to hundreth digit of B + hundreth digit of C

Case 2:

B = 523, C = 532, A = 1055

523 + 532 = 1055 -----> This eqn satisfies the stmt 1 but the hundreth digit of A is not equal to hundreth digit of B + hundreth digit of C

Hence stmt 1 alone is insufficient

Stmts 2:

Units' digit of A = Units' digit of B + Units' digit of C

Two cases - same as above .

Hence stmt 2 is also not sufficient

Combining both stmt 1 and stmt 2:

Two cases - same as above .

We cannot conclude whether the hundreth digit of A is equal to the hundreth digit of B + hundreth digit of C

Hence Insufficient.

pradeepsarathy wrote:IMO E


Stmt 1:

Tens' digit of A = Tens' digit of B + Tens' digit of C

Insufficient - This does not talk about the hundreth digit

Case 1:

B = 123, C = 321, A = 444

123 + 321 = 444 ------> This eqn satisfies the stmt 1 and also, from this we can conclude that the hundreth digit of A is equal to hundreth digit of B + hundreth digit of C

Case 2:

B = 523, C = 532, A = 1055

523 + 532 = 1055 -----> This eqn satisfies the stmt 1 but the hundreth digit of A is not equal to hundreth digit of B + hundreth digit of C

Hence stmt 1 alone is insufficient

Stmts 2:

Units' digit of A = Units' digit of B + Units' digit of C

Two cases - same as above .

Hence stmt 2 is also not sufficient

Combining both stmt 1 and stmt 2:

Two cases - same as above .

We cannot conclude whether the hundreth digit of A is equal to the hundreth digit of B + hundreth digit of C

Hence Insufficient.

In your Case 2 for statement 1:
integer A 1055 is a 4 digit integer which you cannot assume because question stem says that A is a 3 -digit integer.
Answer IMO is A

pradeepsarathy wrote:IMO E


Stmt 1:

Tens' digit of A = Tens' digit of B + Tens' digit of C

Insufficient - This does not talk about the hundreth digit

Case 1:

B = 123, C = 321, A = 444

123 + 321 = 444 ------> This eqn satisfies the stmt 1 and also, from this we can conclude that the hundreth digit of A is equal to hundreth digit of B + hundreth digit of C

Case 2:

B = 523, C = 532, A = 1055

523 + 532 = 1055 -----> This eqn satisfies the stmt 1 but the hundreth digit of A is not equal to hundreth digit of B + hundreth digit of C

Hence stmt 1 alone is insufficient

Please note that A cannot be 1055...as it is given to be 3 digit integer.

goelmohit2002 wrote:A,B and C are 3 digit integers, where A = B + C. Is the hundreds' digit of number A equal to sum of hundreds' digit of B and C ?
1) Tens' digit of A = Tens' digit of B + Tens' digit of C
2) Units' digit of A = Units' digit of B + Units' digit of C

OA = After some discussion.

Think it will be A

shoot...
my bad...missed that part...
yep i agree...i revise my IMO. It's A.
Thanks tohellandback for pointing it out.