(Kaplan) Error in Answer Question

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(Kaplan) Error in Answer Question

by ddirector1 » Wed Aug 11, 2010 9:29 am
Kaplan GMAT Course Book '06-'07 -Question 11- Pg 429- Topical Math Tests.

Here's the question:

Data Sufficiency:

How many nickels does Bill have?

(1): Bill has a total of 17 nickels and dimes.
(2): Bill has $1.30


My answer- C Both 1 and 2 together are sufficient to answer the question

Book answer- E 1 and 2 together are NOT sufficient to answer the question.


My Calculation:

x= nickels y= dimes
x+y= 17

0.05x + 0.10y= 1.30
0.05x+ 0.10 (17-x) = 1.30

X= 8 y=9

Since both are linear equations, they would at most intersect once...so this should be the only answer.

Please confirm that the book answer is wrong. Thx
Source: — Data Sufficiency |

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by kvcpk » Wed Aug 11, 2010 11:38 am
How do you know that $1.3 bill has are only nickels and dimes?

He may be having 1 dollar note. and .30 in terms of nickel and dime.

Hence the statement is insufficient.

Hope this helps!!
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by Ian Stewart » Wed Aug 11, 2010 12:15 pm
Yes, it's E because he might have some quarters or pennies, say. It's not a realistic question though, because the GMAT doesn't expect people to know the names of American coins; that would unfairly advantage American test takers.
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