Relatively easy, but a little tricky

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Relatively easy, but a little tricky

by ani781 » Tue Jun 25, 2013 7:17 pm
Company M ordered a total of 50 printers and computers.
Company N ordered a total of 60 printers and computers.
How many computers did Company M order ?

1) Company M and Company N ordered the same number of computers.
2) Company N ordered 10 more printers than Company M.

Please help resolve this ...

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by faraz_jeddah » Tue Jun 25, 2013 10:18 pm
Let
Pm = Printers ordered by M
Cm = computers ordered by M
Pn = printeres ordered by N
Cn = computeres ordered by N

From the question

Pm + Cm = 50
Pn + Cn = 60

Target question: Value of Cm

Statement 1 :

Cm = Cn

This does not give an exact value.. Cm = Cn = 10, 20 ,30 etc.

Insufficient

Statement 2
Pn = Pm + 10

Again Pm could take different values and still satisfy the 2 equations
Example:
Pm = 10; Pn = 20 ==> Cm = 40
Pm = 20; Pn = 30 ==> Cm = 30

Taking Statements 1 and 2 Together

Pm + Cm = 50 transforms to
(Pn + 10) + Cn = 50

Pn + Cn = 40

but statement 2 => Pn + Cn = 60

There cannot be any solution to the above equation.
Hence both statements are insufficient.

Answer should be E

What is OA?