Easy or tricky question

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Easy or tricky question

by parulmahajan89 » Sun Jun 17, 2012 11:50 am
Bob and Darren are interns in a hospital. Bob spends 40 percent of his hours per week in the pediatrics ward and 30 percent of the remainder of his hours in the lab. Darren spends 20 percent of his hours per week in the pediatrics ward and 10 percent of the remainder of his hours in the lab. How many hours does Darren work per week?

(1) Bob works 20 hours per week in the pediatrics ward.

(2) Darren works 8 hours per week in the lab.


Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.


Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.


BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.


EACH statement ALONE is sufficient.


Statements (1) and (2) TOGETHER are NOT SUFFICIENT
Source: — Data Sufficiency |

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by dimochka » Sun Jun 17, 2012 12:04 pm
Hi,

We can't assume that the interns are both working the same hours (in my opinion). Based on this, there is no connection between Bob's hours / time allocation, and Darren's. Hence choice [spoiler](A)[/spoiler] is irrelevant and does not allow us to solve the question.

Choice [spoiler](B)[/spoiler] is sufficient as we know % of time Darren works in the ward, so we can thus figure out % of time spent in the lab and convert this to actual hours.

Specifically (don't do this extra analysis on the actual exam):
[spoiler]- Darien works 20% of his time in the ward, so Darien works 80% of his time somewhere else
- 10% of this time is spent at the lab -> 80% * 10% = 8%
- If 8% of his time is 8 hours, 100% of his time is 100 hours[/spoiler]

Please confirm OA

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by dhonu121 » Mon Jun 18, 2012 4:14 am
Really easy one.
Clearly to know the absolute value, you need an absolute value.
B is the answer.
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by sandeep_thaparianz » Wed Jun 20, 2012 2:13 am
Easy one +1 for B