The United States will soon begin spot checking all

Question

The United States will soon begin spot checking all shipments of imported coffee for tainting by sandfly larvae. Any coffee found to be so tainted will be destroyed. Officials predict that the spot checks will result in the destruction of approximately 10 percent of all coffee imported into this country. Even so, however, the checks will miss about half of the tainted coffee sent here, since it is estimated that 20 percent of all coffee worldwide is tainted by sandfly larvae.

The author of the passage above is necessarily assuming which one of the following?

Spot inspections will not succeed in preventing unacceptable amounts of tainted coffee from entering the country.
 Inspectors can detect sandfly larvae in only half of the tainted shipments they inspect.
 The proportion of imported coffee tainted by sandfly larvae is representative of the proportion of coffee so tainted worldwide.
 Spot checking will mean that only 10 percent of all imported coffee will be inspected for tainting by sandfly larvae.
 The 80 percent of imported coffee shipments that are not tainted by sandfly larvae should not be inspected.

hogann · Answer

IMO C

Say 100lbs of coffee is important 20lbs "should" be considered tainted. Inspectors will catch 10lbs, and the other assumes the other half (10 more lbs) won't be caught. I have put should in quatation marks because this number is based on the worldwide average. If 30lbs was tainted instead the inspectors would still catch only 10lbs of it however the checks missed 66% of the coffee sent here making the initial claim invalid. We have to assume the same proportions of tainted coffee is shipped worldwide, C covers this.

Economist · Answer

+1 for C.

bml · Answer

IMO C too.

ichha148 · Answer

One more for C

vanilla · Answer

C here as well. What's the OA?

boeinz · Answer

go with C too.

netcaesar · Answer

OA is C.

How you discarded the other options? How justify C?

sprtng · Answer

C is definitely true...read the last sentence of the passage then it says world wide yet we didnt talk about world wide but rather only about the coffee imported to the US, so we need a connection between the two, and C serves this purpose

vanilla · Answer

You can get a clue from the passage"
"...approximately  10 percent  of all coffee imported into this country. Even so, however, the checks will miss about half of the tainted coffee sent here, since it is estimated that  20 percent  of all coffee worldwide is tainted by sandfly larvae."
When CRs post two sets number/% in the stem, you need to check if both co-relate. Often, the passage assumes the general truth as the specific one as in this case.

By the way, what's the source of your CRs?

sprtng · Answer

B states: they inspect some shipments and half of them are tainted, which leads to that they only inspect 20% of the shipments....which is not stated in the passage

ykaiim · Answer

IMO C.

I have a different approach to solve such questions on %ages and Numbers.

Argument is on %ages - 10%, 20%, 50%.
So, all those choices which are dealing with %ages will be right contenders (as per CR Bible). So, A and B are out, but you can check.

D is incorrect because it is not matching with the argument. Nowhere in the argument is it mentioned that the Spot checking will mean that only 10 percent of all imported coffee will be inspected for tainting by sandfly larvae. This is just a case on Extreme+Opposite answer fallcy.

E is incorrect because its language is suggesting something in opposite to the conclusion and falls apart. No such uncertainity is shown in the argument - The 80 percent of imported coffee shipments that are not tainted by sandfly larvae should not be inspected.

achan · Answer

B is derived from C

So C is the correct answer

The United States will soon begin spot checking all

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