Four friends, Charles, Mike, Brian, and John, went on a shopping trip.

Question

Four friends, Charles, Mike, Brian, and John, went on a shopping trip. If Mike spent $400 more than Brian did, John spent $1200 less than Charles did, and Charles spent $400 more than Mike did, how many more dollars did Brian spend than John did?

A. $400
B. $600
C. $800
D. $1000
E. $1200

Kudos for a correct solution.

A. $400
B. $600
C. $800
D. $1000
E. $1200

Kudos for a correct  solution .

chetan2u · Answer

ans A 400.... just substitute the values from 3 possible eq that can be formed

gmat6nplus1 · Answer

M=B+400; J=C-1200; C=400+M. B-J?

J=M+400-1200 --> J=B+400+400-1200 --> J-B=-400 --> B-J=400

Answer A.

EMPOWERgmatRichC · Answer

Hi All,

While most Test Takers would approach this question with Algebra, it can actually be solved rather easily by TESTing VALUES.

We're never given any limitations on how much total money is actually spent, so the individual values (and the total) can be ANYTHING, as long as the values relate to one another as described. So, working through the information that is provided....

IF....
Brian = $1,000
Mike spent $400 more than Brian....

Mike = $1,400

John spent $1,200 less than Charles (we'll come back to this in a moment)

Charles spent $400 more than Mike...
Charles = $1,800

Now, back to the prior info - John spent $1,200 less than Charles...
John = $600

The question asks how many MORE dollars Brian spent than John:
Brian = $1,000
John = $600
$1,000 - $600 = $400

Final Answer:  A

GMAT assassins aren't born, they're made,
Rich

KarishmaB · Answer

As far as possible, stick to using one variable.

Say Brian spent $B.
Mike spent 400+B
Charles spent 400+400+B = 800+B
John spent 800+B - 1200 = B - 400

John spent 400 less than Brian or in other words, Brian spent 400 more than John.

Answer (A)

Bunuel · Answer

VERITAS PREP OFFICIAL SOLUTION:

In this word problem, the first key is to turn the story into equations:

Mike spent $400 more than Brian did: M = 400 + B

John spent $1200 less than Charles did: J = C - 1200

Charles spent $400 more than Mike did: C = 400 + M

Then, in classic GMAT style, the problem doesn't ask you to solve for a single variable, but instead to solve for the difference between B and J ("how many more dollars did Brian spend than John did?"). This means that your goal is to get the equations in terms of B and J so that you can solve for the expression B - J.

Taking the first equation and solving for B, you have B = M - 400.

Taking the second equation and solving for J you have J = C - 1200, and then with the third equation you can replace C with 400 + M so that both B and J are in terms of M: J = (400 + M) - 1200.

So if B = M - 400 and J = M - 800, then:

B - J = (M - 400) - (M - 800)

B - J = M - 400 - M + 800 (remove the parentheses by distributing the multiplication)

B - J = 400, so the answer is A.

PareshGmat · Answer

Answer = A = 400

Charles .................... Mike ................. Brian .................. John

x+800 ........................ x+400 ................ x ........................ x-400 (Let "x" is the expenditure of Brian, all other expenses are calculated with its reference)

Brian spent 400 more than John

Temurkhon · Answer

good approach to express all expense through one variable

Brian: b
Mike: b+400
Charles: b+400+400
John: b+400+400-1200,

so we get B-J=b-(b+400+400-1200)=b-b-400-400+1200=400

A

GMATinsight · Answer

Let, Amounts of Money spent by Four friends, Charles, Mike, Brian, and John are C, M, B and J respectively

M = B + 400--------------Eq(1)
J = C - 1200--------------Eq(2)
C = M + 400--------------Eq(3)
  B - J = ?

Substituting the value of C from Eq(3) in Eq(2)

J = (M+400) - 1200
i.e. J = M - 800
i.e. M = J + 800

Substituting the value of M in Eq(1)

J + 800 = B + 400
i.e. B - J = 800-400 = 400

Answer: option  A

rhine29388 · Answer

consider money spent by brian as $x 
so money spent by mike is $x +$400
money spent by charles is $x +$800
money spent by john is $x - $400
therefore brian spent $ 400 more than john did
hence answer option A

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Four friends, Charles, Mike, Brian, and John, went on a shopping trip.

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