numberline

IMO - 'A'

Statement says that the distance between A and B is 25. It is already given that the distance between A and C is 5 and between C and B is 20. Hence, from the 1st statement it is clear that B is on the opp side of C, than A. Hence, Statement is SUFFICIENT

However, statement 2 gives information about only 2 of them. Hence insufficient.

i solved it this way but got wrong ..can any1 explain why

distance b.w A &C is 5
there could be possibiltes

case1 0.....A...................C
case2 A........C..........0

case3 C.......0........A

now stmt 1

case1 :
2 ways

B.............................0.............A.......C
0......A...........C............................B

case 2
B..................A.........C........0
A.....C.........0..................................B

case 3
B.........................C..........0................A
C............0............A........................B


So, Insuff


STmt 2 : As seen above....B could be left or right

So, Insufff...where i am making mistake ?????????

You forgot case 4

A.....0.......C

Neways, is there a specific reason why you are even considering 0 in this case?

The mistake your making is in Case 3:-

"C............0............A........................B "

This is not correct.

ac = 5
cb = 20.........given

is we take those 2 and according to your representation, AB = 15.
But it is given to be 25. Hence, this case is wrong with reference to this stmnt.

the reason i chose 0 is because, a & c can be at either side of num line.
I rem cramya was solving a ques like this

Crmaya : u r help req...where i am going wrong

vivek.kapoor83 wrote:i solved it this way but got wrong ..can any1 explain why

distance b.w A &C is 5
there could be possibiltes

case1 0.....A...................C
case2 A........C..........0

case3 C.......0........A

now stmt 1

case1 :
2 ways

B.............................0.............A.......C
0......A...........C............................B

case 2
B..................A.........C........0
A.....C.........0..................................B

case 3
B.........................C..........0................A
C............0............A........................B


So, Insuff


STmt 2 : As seen above....B could be left or right

So, Insufff...where i am making mistake ?????????

from Q (question + statements)
dist B~C=20
dist A~C=5
dist B~A=25

case1 :
2 ways

B.............................0.............A.......C
0......A...........C............................B

2way not possible
the first possibility is wrong as B~A becomes less than B~C. Contadicts Q

case 2
B..................A.........C........0
A.....C.........0..................................B

Again 2 ways not possible
the first possibility is wrong as B~A becomes less than B~C. Contadicts Q

case 3
B.........................C..........0................A
C............0............A........................B

Again 2 ways not possible
the 2nd possibility is wrong as B~A becomes less than B~C. Contadicts Q

This is an absolute value problem.

Question:

IA-CI =5 and IB-CI = 20

St1 ) IA-BI = 25, there are two ways to get this

A-C + C-B OR C-A + B-C

For the first one A-C=5 and C-B=20 so A=5+C and C=B+20

B-----------C---------A

For the second one C-A =5 and B-C =20 so C=A+5 and B=C+20

A-----------C---------B

SUF

ST2) B-A > 0

From the given , we can get B-A as:

B-C + C-A = 20+5 or 20-5

So B-C = 20 and C-A=5 MEANS B=C+20 and C=A+5

A---C-------------B

OR

B-C = 20 and A-C= -5 MEANS B=C+20 and A=C-5

C---A------------B


INSUF


I would choose A and pray not to see this question in GMAT

cramya,
i solved it the way u did .........in ur previous posts...is that the right approch

Vivek,

in the earlier question, as far as i remember, it asked if one of these numbers was positive or negative...hence the zero was essential

It doesn't ask so here, hence this is much easier...

You can use the visual representation, that is fine and useful too, however using zero here just adds to the complexity of the problem.

Hope that helps you out.