please explain gmat prep question

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please explain gmat prep question

by yvonne12 » Mon Apr 02, 2007 10:51 am
In addition table shown, what is the value of m + n?
+ x y z
__________

4 1 -5 m

e 7 n 10

f 2 -4 5

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Re: please explain gmat prep question

by ajith » Mon Apr 02, 2007 5:06 pm
Could you please format the table , probably as a picture so that people can help you, and please specify the source of the problem.
thanks,
Ajith
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reply

by yvonne12 » Tue Apr 03, 2007 9:32 am
I dont know how else to format it. This is exaclty how it is in the gmat prep.


In addition table shown, what is the value of m + n?
+ x y z
__________

4 1 -5 m

e 7 n 10

f 2 -4 5

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Re: reply

by gabriel » Tue Apr 03, 2007 11:01 am
yvonne12 wrote:I dont know how else to format it. This is exaclty how it is in the gmat prep.


In addition table shown, what is the value of m + n?
+ x y z
__________

4 1 -5 m

e 7 n 10

f 2 -4 5

well u culd have created an attachment for it ...nywayz i think i got the problem.... the q asks for m+n...

acccording to the addition table ...

4+z=m....(1)
4+y=-5..... (2)
4+x=1....(3)


i hope by now u have understood how the table works ....

from eqn 3 we get x=-3.....from eqn 2 we get y=-9

now again from the table we get

e+x=7......(4)
e+y=n.....(5)
e+z=10.....(6)

now from eqn 4 we have e=7-x=7-(-3)=10 ... substituting value of e and y in eqn 5 we get ... 10 - 9 =1=n


from eqn 6 we get ... z=10-e=10 -10=0 .... substituting this value of z in eqn 1 we get ...4+0=m=4

so finally .... m=4 and n=1 ... therefore m+n=4+1=5 .....

it really is not as complicated as it looks ... just a matter of figuring out how the table works and making some simple eqn

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thanks

by yvonne12 » Wed Apr 04, 2007 11:34 am
Thanks , you're right I guess the variables in the table intimidated me. Thanks again