Carrie, Lisa, and Betty

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Carrie, Lisa, and Betty

by BTGmoderatorDC » Wed Jan 03, 2018 3:55 am
Carrie, Lisa, and Betty all make purchases at a music store that sells all records for a certain price and all CDs for a certain price. How much does Carrie pay for 1 record and 2 CDs?

(1) Lisa bought 3 records for $22.50.

(2) Betty bought 2 records and 4 CDs for $55.00.

Isn't statement 1 sufficient?

OA B

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by DavidG@VeritasPrep » Wed Jan 03, 2018 4:29 pm
lheiannie07 wrote:Carrie, Lisa, and Betty all make purchases at a music store that sells all records for a certain price and all CDs for a certain price. How much does Carrie pay for 1 record and 2 CDs?

(1) Lisa bought 3 records for $22.50.

(2) Betty bought 2 records and 4 CDs for $55.00.

Isn't statement 1 sufficient?

OA B
Think about it algebraically: call the cost of one record "R" and the cost of one CD "C." The cost of one record and two CD's would be R + 2C.

Statement 1: 3R = 22.50. Allows us to solve for R, but nothing about C. Not Sufficient.

Statement 2: 2R + 4C = $55.00
Divide both sides by 2 to get R + 2C = $27.50. Because we have a unique value for R + 2C this statement alone is sufficient. The answer is B
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