A complicated math, pls help to explain

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A complicated math, pls help to explain

by tracyyahoo » Sat Sep 03, 2011 4:17 am
From 1985 to 1994, what was the percent increase in total united states trade?

(1) Total united state trade in 1985 was 17percent of gross domestic product in 1985.
(2) Total united state trade in 1994 was 23percent of gross domestic product in 1994.

why is not C, uh??pls explain!!!
Source: — Data Sufficiency |

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by Ian Stewart » Sat Sep 03, 2011 8:48 am
tracyyahoo wrote: why is not C, uh??pls explain!!!
Because the Gross Domestic Product may have changed from 1985 to 1994. If, say, the GDP in 1985 was $100, and in 1994 it was $1,000,000, then the percent increase in US trade would be enormous (it would have increased from $17 to $230,000). If instead, the GDP was $100 in both 1985 and 1994, then the percent increase in US trade would be quite small. So the answer is E.

That said, I think it's a badly designed question. Where is it from? The US GDP in 1985 and 1994 are both real world numbers - they aren't unknowns. Since a test taker might think 'I could look up the values for US GDP in 1985 and 1994 and therefore solve the question with both statements', the question writer ought to have used a fictional country in the question.
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by GmatKiss » Sat Sep 03, 2011 12:21 pm
tracyyahoo wrote:From 1985 to 1994, what was the percent increase in total united states trade?

(1) Total united state trade in 1985 was 17percent of gross domestic product in 1985.
(2) Total united state trade in 1994 was 23percent of gross domestic product in 1994.

why is not C, uh??pls explain!!!
We are asked about the total increase in trade from 1985-1994

1. only 1985 - Insuff
2. only 1994 - Insuff
1+2 - 1985 + 1994 - Insuff

E[/spoiler]

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by prateek_guy2004 » Sat Sep 03, 2011 12:22 pm
From 1985 to 1994, what was the percent increase in total united states trade?

(1) Total united state trade in 1985 was 17percent of gross domestic product in 1985.

the ques is clearly asking about the % increase..To get a percentage you need total amount of trade, From the old amount to the new increased amount...Thats how we get %.

statement 1 not sufficient

(2) Total united state trade in 1994 was 23percent of gross domestic product in 1994.

same old story with this one.
statement 1 not sufficient

even after concluding both statements getting the original amount is not possible.

Hence E
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