How many papers can Bill and Tim proofread in 60 minutes if they are working together?
(1) Bill can proofread twice as many papers as Tim in the same time period.
(2) Tim can proofread 30 fewer papers than Bill in 60 minutes.
How to determine which statement is sufficient?
How many papers can Bill and Tim proofread in 60 minutes if
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Say Bill proofread b number of papers in 60", while Tim does t in 60".ardz24 wrote:How many papers can Bill and Tim proofread in 60 minutes if they are working together?
(1) Bill can proofread twice as many papers as Tim in the same time period.
(2) Tim can proofread 30 fewer papers than Bill in 60 minutes.
How to determine which statement is sufficient?
We have to find out the value of (b + t).
Statement 1: Bill can proofread twice as many papers as Tim in the same time period.
=> b = 2t. Clearly, insufficient.
Statement 2: Tim can proofread 30 fewer papers than Bill in 60 minutes.
=> t = b - 30. Clearly, insufficient.
Statement 1 & 2:
From b = 2t and t = b - 30, we get b = 60 and t = 30, thus, (b + t) = 90 papers. Sufficient.
The correct answer: C
Hope this helps!
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