How many diamond rings can a goldsmith refine in two weeks?

Question

(1) There are 4 diamonds in each ring.
(2) One goldsmith can refine 2 diamonds in 4 hours.

jasimuddin · Answer

STEM:# of rings refined in 2 weeks=?

STAT-1: a ring contains 4 diamonds. No information about hours and days ......insufficient.

STAT-2: 4 hours is needed to refine 2 diamonds......insufficient

COMB-1&2: goldsmith needs 8 hours to refine a ring.
But we don't know how many hours a day and how many days a week goldsmith works......insufficient

ANS: E

rakaisraka · Answer

Hi bunuel what is the right answer - I dont think gien answer is right

Kurtosis · Answer

Hi,

The OA is correct.

Number of diamond rings refined in 2 weeks = ?

St1: There are 4 diamonds in each ring --> Clearly insufficient

St2: One goldsmith can refine 2 diamonds in 4 hours. --> Rate = 2 per 4 hrs = 12 diamonds/day
We know the number of diamonds but we do have no information about the number of diamond rings.
Not Sufficient

Combining St1 and St2: 
4 diamonds in 1 ring --> 3 diamond rings/day --> 42 diamond rings in 2 weeks

Answer: C

5achin · Answer

Is it ok to assume number of working days & hours of the week in such a question?

Kurtosis · Answer

We are given a specified rate. The number of days in a week and the number of hours in a day are constant. We are not assuming anything that is out of our perceived knowledge.

5achin · Answer

What i meant to ask is, should this type of question be viewed as a trick question (wherein the 'manhours' to be considered is not specified ) or just calculate assuming the goldsmith works for 24 hrs/day 7 days a week straight?

sivaspurthy · Answer

Hi
This seems to be an ambiguous question....no of hrs in a day assumed that 24 hrs the gold smith keeps on working....no of diamonds needed to be polished is 4 ...what about the ring part to be polished apart from diamonds...???...may be i m thinking too much

KarishmaB · Answer

Yes, the question doesn't seem to be GMAT-Quality.

1. We do not know that to "refine a ring", all we need to do is "refine the diamonds in the ring" though the solution assumes that.

2. The rate is given in terms of diamonds per hour but time is in weeks. A rate in terms of diamonds per day would make far more sense (though I would still wonder if it works 7 days a week). OR the question needs to specify that the refinery works 24 hrs/7 days etc.

In any case, there is ambiguity in the question.

How many diamond rings can a goldsmith refine in two weeks?

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