Island Museum and artifacts found on the Kaxna Islands

[Sinta]

Hi.

Please review the questions stem here:
http://www.mba.com/the-gmat/nex-gen/sam ... 6?next=yes

My problem is with the second set of items (7 wooden statues and 20 metal implements) OA is yes

The explanation at gmat-perp says that since:
15R+4T = 7000 (R= radiocarbon tests, T=TL tests)
it follows that 7R<3500

cay anyone explain?

[StaceyKoprince]

Hi, Sinta

Congrats on being our first IR poster! I just posted some guidelines (after you'd already posted), so just note for future that you will have to include the question stem (not the entire problem - just the question itself) and the answer choices in the body of your post.

I'll put it in for you this time. Another note: you do have to put in all 3 statements even if you have a question only about one. (This thread will now be the permanent thread for anyone with a question about the "Kaxna" prompt - so we want all 3 statements there for future use.)

For each of the following combinations of Kaxna artifacts, select Yes if, based on the information provided, the cost of all pertinent techniques described can be shown to be within the museum's first-year Kaxna budget. Otherwise, select No.

(1) 2 bone implements and 5 fired-clay cups decorated with gold
(2) 7 wooden statues and 20 metal implements
(3) 15 wooden statues decorated with bone

Okay, here we go. The passage gave us various pieces of cost info about testing different objects. Tab 3 tells us that $7,000 = 4 TL tests + 15 RC tests and that $7,000 = 40 ICP-MS tests. We don't have to worry about IRMS tests at all - they're not part of the budget.

The last sentence in Tab 3 is crucially important: "For each technique applied by an outside lab, the musem is charged a fixed price per artifact."

So there's a fixed price for an ICP-MS test, a fixed price for a TL test, etc.

Tab 1 tells us that ICP-MS is used to test metal artifacts. The second statement in the question indicates that we have 20 metal artifacts, so if it costs $7,000 to test 30 metal artifacts, then testing 20 will take half of our money, or $3,500. We have $3,500 left to do the rest of the testing.

So what can we figure out about the 7 wooden artifacts? Remember that we know that, whatever the price is for a wooden artifact, it's the same for ALL wooden artifacts.

Tab 1 tells us that wooden artifacts are tested using radiocarbon dating. Tab 3 tells us that $7,000 = 4 TL tests + 15 RC tests. Let's say that those 4 TL tests cost almost nothing - a penny each. In fact, I'm going to keep the overall cost at $7,000, but just eliminate TL from the equation: it costs $7,000 to do 15 RC tests. Each RC test has to cost the same - tab 3 told me that.

So if I only need to do 7 RC tests, that's a bit less than half of the 15 tests I'm allowed. The cost, then, will also be a bit less than half of $7,000, or less than $3,500.

Total, then, I'm spending $3,500 + <$3,500, or < $7,000. Statement 2 can be shown to be true using the available info, so the answer to that one is Yes.

[Sinta]

Thanks!!

[tim]

:)

[zishanpurple]

Thanks for the answer.

But I am still confused as to what does "$7000 - equal to 4 TL tests plus 15 Radiocarbon tests" means. It certainly does not mean that $7000 can cover 4TL or 15 Radiocarbon tests.

To me it appears that as we do not know how much each TL and each Radiocarbon test costs, we can not determine the cost of 2TLs or 3 TLs.

Please explain.

Many thanks,
Zishan

[tim]

$7000 can cover 4TL AND 15 Radiocarbon tests. This is enough to cover 2 TLs or 3TLs. Does this answer your question?

[zishanpurple]

I think it does. I got confused :(

It is like 4TL + 15 RT = $7000
=> 15 RT < $7000
=> 7.5 RT < $3500
So 7RT < $3500.

Many thanks!

[RonPurewal]

good.

make sure you notice what they're doing: they're giving you something that's quite hard to solve with "textbook math", but that's pretty straightforward to understand intuitively.

as an analogy, let's say i can buy 10 hot dogs and 5 packets of sauce for $20 ... then i know for sure that 5 hot dogs will cost $10 or less.

[heyazhi09]

Hello I get confused to a question.

For each of the following results of tests performed on Kaxna artifacts, select Yes if, based on the museum's assumptions, the result confirms that the artifacts was created during the time of the Kaxna Kingdom. Otherwise, select No.

1) Bone necklace shown by IRMS to have element ratios characteristic of artifacts known to be from the Kaxna Kingdom.

2)Fired-clay jug dated to 1050 BC by TL dating

3)Copper box shown by ICP-MS to have the same ratio of trace metals found in the copper mines of Kaxna.


My question is why 1) and 3) are both wrong?

Although IRMS and ICP-MS cannot tell us the date, we can indirectly know the date. Because by these techniques, we can know that the bone in 1) and copper in 3) are the artifacts in K.
So the date is of 1250-850 BC.


Can anyone help me?
Many thanks.

[tim]

what tells you that we can indirectly know the date? IRMS and ICP-MS give no indication that they can tell us anything about the dates of artifacts..

[heyazhi09]

what tells you that we can indirectly know the date? IRMS and ICP-MS give no indication that they can tell us anything about the dates of artifacts..

If we know the artifacts were produced in Kaxna, we can know their dates. Right? According to "Techniques", we can know that Bone necklace shown by IRMS was produced in Kaxna Kingdom.

Also, Copper box shown by ICO-MS can be inferred to be produced in K.

Since they are both produced in Kaxna, and Kaxna is from 1250-850 BC, they are dated from 1250-850 BC too.

Do I wrongly understand this question? if yes, plz correct me. thanks in advance.

[tim]

yes you are misunderstanding this one. just because the artifacts were found in a particular location does not mean they were created during the time of a specific kingdom. there is absolutely no connection here..

[RonPurewal]

the problem lies in how you're reading the text.

for instance, the text of #1 says this:

element ratios characteristic of artifacts known to be from the Kaxna Kingdom

you're reading this and (mistakenly) thinking it means that the stuff is actually from kaxna. it's not, necessarily -- it just has a similar element ratio.

analogy:
my brother is wearing a suit with a cut similar to that of Italian suits.
--> this doesn't mean that my brother is wearing an italian suit.

[heyazhi09]

Great explanation!

Thanks, Ron and Tim.

[tim]

:)