Bea owns how many more CDs than Al owns?

Question

(1) If Bea gives 9 of her CDs to Al, then Al will own twice as many CDs as Bea owns.

(2) If Bea gives 1 CD to Al, and Al purchases 4 additional CDs, then Al and Bea will have an equal number of CDs.

Kudos for a correct  solution .

Celerma · Answer

We need x-y=? x is Bea's number of CDs and Al has y.
Statement A: 2(x-9)=y+9 NS

Statement B: x-1=y+1+4 so we can get the difference between x and y. Sufficient.

Answer is B

peachfuzz · Answer

B-A=?

Statement 1 :
2 (B-9) = (A+9)
2B-A=27
Insufficient

Statement 2 :
B-1=A+5
B-A=6
Sufficient

Answer : B

Lucky2783 · Answer

(1) If Bea gives 9 of her CDs to Al, then Al will own twice as many CDs as Bea owns.
  B= \frac{A+27}{2} 
 This looks like a average question where B is average of A and 27 , till we have A <27 we will have B>A.
 At A=27 B=27 
 as we move up A we will start getting A>B . 
 Not Sufficient. 
(2) If Bea gives 1 CD to Al, and Al purchases 4 additional CDs, then Al and Bea will have an equal number of CDs.
 Sufficient .
 B-1 = A+5

Answer B.

dream21 · Answer

!) 2(B-9) = A+9
 2B- A = 27 Not Sufficient

2) B-1 = A+5
 B-A = 6 Sufficient

Ans B

Bunuel · Answer

MAGOOSH OFFICIAL SOLUTION: cdsforalandbea_text.png

Serch · Answer

Could you please explain how you got the formula:

2(B-9) = A+9

It is not clear for me. Thanks

Serch · Answer

Hi, could you please explain how you got the formula:

2(B-9) = A+9

It is not clear for me. Thanks

amanvermagmat · Answer

Hello

Lets say Al owns 'A' CDs and Bea owns 'B' CDs. 
If B gives 9 of her CDs to Al, number of CDs now remaining with Bea = B-9, and number of CDs now with Al = A+9. This is the new number of CDs with them.
And we are given that in this new scenario, Al now owns twice as many CDs as Bea.

So number of CDs with Al now = 2 * number of CDs with Bea now
OR (A+9) = 2(B-9)

BrentGMATPrepNow · Answer

Let A = number of CDs Al owns
Let B = number of CDs Bea owns

Target question :    What is the value of B - A?

Statement 1 : If Bea gives 9 of her CDs to Al, then Al will own twice as many CDs as Bea owns.  
We can create the equation: 2(B - 9) = A+9 
Expand left side to get 2B - 18 = A+9 
Rearrange to get: 2B - A = 27 
This does not tell us  the value of B - A . 
Since we cannot answer the  target question  with certainty, statement 1 is NOT SUFFICIENT

Statement 2 : If Bea gives 1 CD to Al, and Al purchases 4 additional CDs, then Al and Bea will have an equal number of CDs 
We can create the equation: B - 1 = (A + 1) +4 
Simplify this to get  B - A = 6  
Since we can answer the  target question  with certainty, statement 2 is SUFFICIENT

Answer: B

Cheers,
Brent

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Bea owns how many more CDs than Al owns?

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Bea owns how many more CDs than Al owns?

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