A certain expressway has Exits J, K, L, and M, in that order. What is

Question

A certain expressway has Exits J, K, L, and M, in that order. What is the road distance from Exit K to Exit L ?

(1) The road distance from Exit J to Exit L is 21 kilometers.
(2) The road distance from Exit K to Exit M is 26 kilometers.

Bunuel · Accepted Answer

SOLUTION

A certain expressway has Exits J, K, L, and M, in that order. What is the road distance from Exit K to Exit L ?

(1) The road distance from Exit J to Exit L is 21 kilometers. JL=21, so JK+KL=21. Not sufficient.
(2) The road distance from Exit K to Exit M is 26 kilometers. KM=26, so KL+LM=26. Not sufficient.

(1)+(2) We have two distinct linear equations with three unknowns, hence we cannot solve for any of them. Not sufficient.

Answer: E.

Zenverse · Answer

J-K-L-M

We know the distance between J and L
We know the distance between K and M

Neither of these tells us anything about the distance between K and L -> A, B, D incorrect
The two statements put together allso tell us nothing about the distance between K and L -> C incorrect

E is correct

Look at this another way, taking a dash for 5 units, and approximating, you can diagram (I) and (II) together as:
J---K-L----M
OR
J--K--L---M
OR
J-K---L--M

Hence E

I don't have a simpler explanation, I'm afraid.

Reni · Answer

Can`t I say (1)+(2):

(1)JL + LM = 21+LM
(2)KM +KJ = 26 + KJ
(1)+(2) = 21+Lm = 26+KJ
LM-KJ = 5
so KL=5 ?

Bunuel · Answer

The point is that LM - KJ does NOT equal to KL.

JeffTargetTestPrep · Answer

Solution:

Let's first put the given information into a diagram. We can also define variables for the distances between J and K, K and L, and L and M.

Distance from J to K = x

Distance from K to L = y

Distance from L to M = z

https://i.imgur.com/jxvolQU.png

We are asked to determine the road distance from Exit K to Exit L. Thus, we need to determine the value of y.

Statement One Alone:

The road distance from Exit J to Exit L is 21 kilometers.

Statement one tells us that x + y = 21.

This is not enough information to answer the question. Statement one alone is not sufficient. Eliminate answer choices A and D.

Statement Two Alone:

The road distance from Exit K to Exit M is 26 kilometers.

Statement two tells us that y + z = 26.

This is not enough information to answer the question. Statement two alone is not sufficient. Eliminate answer choice B.

Statements One and Two Together:

From statements one and two we know the following:

x + y = 21 and y + z = 26

Since this is not enough to determine the value of y, we cannot answer the question.

Answer: E

bumpbot · Answer

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A certain expressway has Exits J, K, L, and M, in that order. What is

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