a, b, c, and d lie on the number line such that a

Question

a, b, c, and d lie on the number line such that  a < b . What is the value of  \frac{(a-b)}{(c+d)}  ?

1. c lies exactly between a and b.
2. d lies exactly between a and c.

Source: Experts Global

chetan2u · Answer

a, b, c, and d lie on the number line such that  a < b . What is the value of  \frac{(a-b)}{(c+d)}  ?

1. c lies exactly between a and b.

2. d lies exactly between a and c.

There are FOUR variables and NO numeric value. There is no relation between all four such that the variables get cancelled out from the fraction 
Don't get overwhelmed with variables. press E immediately if something of this sort comes in actuals

E

Vinodhini1803 · Answer

I feel answer is C..Since 
if we take a = 0, and d = x then C = 2x and b = 4x
then a-b = -4x
and c + d = 3x 
answer is -4/3. 
where am I going wrong

chetan2u , Kindly help

chetan2u · Answer

You can’t assume any values. So taking a=0 is not correct. 
a could be 10, then the answer will change. 
a could be 5, 100, anything.

Hoozan · Answer

We could use the concept of ratios out here. If a/c is one ratio and if we add/sub two different constants, in this case b and d to the numerator and the denominator, we will get a different ratio. And this ratio will keep changing based on the constants we add or subtract.

Twin Question: https://gmatclub.com/forum/if-a-b-c-and ... 48920.html

CEdward · Answer

I hope GMAT doesn't throw stuff like this on the exam...huge time wasters that just gets people spinning about a possible solution. It's clear there isn't any, but then self doubt creeps in and voila, I wasted 2-3 minutes.

ItsTym · Answer

a, b, c, and d lie on the number line such that a<b. What is the value of (a-b)/(c+d)?

As per question 
Let assume a, b= a+x (as b>a)

1. c lies exactly between a and b.
C= a+x/2,
Can not solve so not sufficient

2. d lies exactly between a and c.

d = (a+ (a+x/2))/2
d= a+x/4
So alone is not sufficient.

Combine 1 & 2..
C= a+x/2, d= a+x/4
C+d= 2a+3x/4
a-b= -x

(a-b)/(c+d)= -x/(2a+3x/4)... Can not solve further..so I sufficient

IMO E

Posted from my mobile device

bumpbot · Answer

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a, b, c, and d lie on the number line such that a < b.

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