Video cameras

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Video cameras

by pepeprepa » Sun Aug 24, 2008 4:58 am
A manufacturer produced x percent more video cameras in 1994 than in 1993 and y percent more video cameras in 1995 than in 1994. If the manufacturer produced 1.000 video cameras in 1993, how many video cameras did the manufacturer produce in 1995?
1) xy=20
2) x + y + (xy)/100 = 9.2

This made me learn some things so I copy it to you.

OA: B
Last edited by pepeprepa on Sun Aug 24, 2008 11:03 am, edited 2 times in total.

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by parallel_chase » Sun Aug 24, 2008 10:30 am
I think the answer should be B.

question stem:
1000----1993
x(1000)/100 + 1000=> 10x +1000 -----1994
y/100(10x+1000) + 10x+1000=> (xy)/10 +10y +10x +1000 =>1995



Statement I

xy=20

we need individual values for x and y.

Insufficient.

Statement II

100x+100y+xy = 9.2*100
100x+100y+xy=920

(xy)/10 +10y +10x +1000 =>1995

(xy+100y+100x)/10 + 1000
920/10 + 1000 = 1092

Hence B is the answer.

What's the OA?

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by pepeprepa » Sun Aug 24, 2008 11:03 am
You are right!

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by parallel_chase » Sun Aug 24, 2008 11:05 am
pepeprepa wrote:This made me learn some things so I copy it to you.
pepeprepa I am more interested in the above statement rather than the question.

Would love to know those things.

Thanks.

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by hwiya320 » Sun Dec 07, 2008 3:15 pm
parallel_chase wrote:I think the answer should be B.

question stem:
1000----1993
x(1000)/100 + 1000=> 10x +1000 -----1994
y/100(10x+1000) + 10x+1000=> (xy)/10 +10y +10x +1000 =>1995


Statement I

xy=20

we need individual values for x and y.

Insufficient.

Statement II

100x+100y+xy = 9.2*100
100x+100y+xy=920

(xy)/10 +10y +10x +1000 =>1995

(xy+100y+100x)/10 + 1000
920/10 + 1000 = 1092

Hence B is the answer.

What's the OA?
Could you please show me how the bolded statement was created?

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by kris610 » Sun Dec 07, 2008 3:36 pm
Stem says the number of video cameras in 1995 was:

1000(1+X/100)(1+Y/100).

Expand 1000(1+X/100+Y/100+XY/10^4).

B gives you X/100+Y/100+XY/10^4. Plug that in and you get the answer.