In 1990, nearly 80% of people in the United States reported

Question

In 1990, nearly 80% of people in the United States reported that they knew someone who had been diagnosed with cancer. In 2010, that percentage remained unchanged yet cancer incidence rates in the population increased by over 40% from 1990 to 2010.

Which of the following, if true, would best explain how the percentage of people who knew someone with cancer could have remained unchanged despite the dramatic increase in the incidence of cancer?
 
A. Improved treatment options dramatically reduced cancer mortality rates from 1990 to 2010.
 
B. From 1990 to 2010, most new cases of cancer occurred in densely populated urban centers with previously high cancer rates.
 
C. Many of the new cancer cases from 1990 to 2010 occurred in geographically isolated regions where little or no cancer had been present before.
 
D. From 1990 to 2010, some of the new cancer cases occurred in people who had previously been diagnosed with another form of cancer.
 
E. Because of dramatic technological improvements in diagnostic tools from 1990 to 2010, cancer was more likely to be diagnosed in 2010 than in 1990.

ssbisht · Accepted Answer

Fact1 : 1990- nearly 80% of people in the United States reported that they knew someone who had been diagnosed with cancer
Fact2 : 2010- nearly 80% of people in the United States reported that they knew someone who had been diagnosed with cancer
Fact3 : cancer incidence rates in the population increased by over 40% from 1990 to 2010.

Now a way the percentage of people who knew someone with cancer could have remained unchanged despite the dramatic increase in the incidence of cancer is that the cases of new cancer are known to people who already know somebody with cancer.
This is the scenario in Choice B as in a densely populated urban center a lot of people will be knowing each other and hence number of people who knows many cancer patients will be common.

A. Improved treatment options dramatically reduced cancer mortality rates from 1990 to 2010.
Incorrect : Irrelevant

B. From 1990 to 2010, most new cases of cancer occurred in densely populated urban centers with previously high cancer rates.
 Correct: In a densely populated urban center a lot of people will be knowing each other and hence number of people who knows many cancer patients will be common.

C. Many of the new cancer cases from 1990 to 2010 occurred in geographically isolated regions where little or no cancer had been present before.
Incorrect: This will increase the people who know a cancer patient.

D. From 1990 to 2010, some of the new cancer cases occurred in people who had previously been diagnosed with another form of cancer.
Incorrect as talks about some of the cancer cases while the increase is around 40%.

E. Because of dramatic technological improvements in diagnostic tools from 1990 to 2010, cancer was more likely to be diagnosed in 2010 than in 1990.
Incorrect : Doesn’t help in knowing why percentage people knowing cancer patient haven’t changed.

aditya111 · Answer

B. From 1990 to 2010, most new cases of cancer occurred in densely populated urban centers with previously high cancer rates.
 Correct: In a densely populated urban center a lot of people will be knowing each other and hence number of people who knows many cancer patients will be common.

I believe we cannot come to the conclusion that the total number of people one knows will remain common in densely populated areas.

and in C 
If a person in isolated area is diagnosed with cancer then no person will get to know about this incident and the 80 percent will remail common

and in D. 
If the same person is diagnosed with multiple cancers then the chances are that the total number of people suffering with cancer will remail unchanged and the cancer incidence will increase.

Please give your inputs also for a healthy discussion. :D

ssbisht · Answer

Hi Aditya,

See my logic in bold:

B. From 1990 to 2010, most new cases of cancer occurred in densely populated urban centers with previously high cancer rates.
 Correct: In a densely populated urban center a lot of people will be knowing each other and hence number of people who knows many cancer patients will be common. 
I believe we cannot come to the conclusion that the total number of people one knows will remain common in densely populated areas.

If you read choice B carefully it says - in densely populated urban centers with previously high cancer rates.
Now in a densely populated area with high cancer rates chances of a person knowing somebody suffering with cancer should be already very high.

and in C 
If a person in isolated area is diagnosed with cancer then no person will get to know about this incident and the 80 percent will remail common
 
The complete sentence in choice C is - Many of the new cancer cases from 1990 to 2010 occurred in geographically isolated regions where little or no cancer had been present before.
If little or no cancer had been present before than any new cancer case is bound to increase the number of people who knows someone suffering from cancer.

and in D. 
If the same person is diagnosed with multiple cancers then the chances are that the total number of people suffering with cancer will remain unchanged and the cancer incidence will increase.
 
If same person is diagnosed with multiple cancers it will still count as one cancer case.
Cancer incidence rates in population means the number of people with reported cancer in the population.

The author has tried to put a scenerio here and asked us to choose the best choice.
I beleive above point will help to make it clear to you.

Thanks

IvyLeague56 · Answer

i ended up answering (C). However i do understand now that the answer is (B). Good question indeed !

jlgdr · Answer

Nice question Stuck between B and D Any ideas? Pqhai shed some light over here buddy Cheers J

ssriva2 · Answer

Intially choosen C but now understood why B is correct answer.
Good question.

PathFinder007 · Answer

hi  mikemcgarry

could you please provide your comments on this.

This is an paradox question. according to option C we can say cancer has increased in isolated geographical areas. so we can say very less people know each other. so over all number of cancer patients has increased but still the % is same. could you please clarify this.

Regards

samusa · Answer

Option C states that there is no history of cancer in the stated geographically isolated regions.
So if in such areas someone develops cancer, then the local people there will come to know about cancer.So, the overall percentage should be more than 80% because new set of people have been added to the category of people who know someone with cancer.But that will be against the premise which states that the percentage remained steady at 80%.

I DONOT MIND KUOD S

Nevernevergiveup · Answer

Original Explanation:

This problem contains a paradox that you must explain: how could the number of cancer case increase dramatically, yet the percentage of people who know someone with cancer remain the same. One way is if most new cancer cases occur where people are more likely to already know someone with cancer. Then the number of cases would go up but there would be no new people added who know someone with cancer. Answer choice (B) maps out just that possibility and thus removes the paradox. In answer choice (A), cancer mortality does not relate to the given paradox so (A) is not correct. Answer choice (C) is the opposite of correct answer (B) and increases the paradox. If most of the new cancer cases occurred in places where few people knew someone with cancer, then you would really expect the 80% figure to go up. In (D) the word “some” immediately eliminates it as a possible choice because if only one of the new cases occurred in someone who had it before, it would have no effect on the paradox (remember some can mean anything from one to all). In (E), the likelihood of diagnosis does not affect the paradox at all. Answer is (B).

1Narrative · Answer

ANSWER CHOICE D???????

IS IT NECESSARILY TRUE THAT IN A DENSELY POPULATED URBAN CENTER A LOT OF PEOPLE WILL KNOW EACH OTHER AND HENCE THE NUMBER OF PEOPLE WHO KNOW MANY CANCER PATIENTS WILL BE COMMON?

sayantanc2k · Answer

This is not an inference type question, hence the condition "necessarily true" does not need to be satisfied. But it could possibly be the case that "IN A DENSELY POPULATED URBAN CENTER A LOT OF PEOPLE WILL KNOW EACH OTHER AND HENCE THE NUMBER OF PEOPLE WHO KNOW MANY CANCER PATIENTS WILL BE COMMON". Hence option B could be an explanation of the discrepancy.

You are asked to find the best explanation among the given options, and option B does so the best. D could be an explanation, but it is unlikely that the number of patients who are diagnosed with cancer and had already had some other form of cancer is as high as 40% of the existing cancer patients. "SOME of the new cancer cases occurred.... " does not justify such high percentage. In absence of B, D could be the answer.

StoicBread · Answer

D. From 1990 to 2010,  some  of the new cancer cases occurred in people who had previously been diagnosed with another form of cancer.

Whenever two answers seem like they could be correct (B and D), I look if one of the potential answers uses a word like  some . If so, I go with the other...

chesstitans · Answer

this question focuses on testing the ability to sense the logic behind the explanation. For my money, the question is really interesting.

HappyQuakka · Answer

Hmm I was torn between B and D, and decided to go with B.

D sounds ok, but only some of the newly diagnosed cancer happened to people who already had some other form of cancer.
B is better per network theory - high frequency in densely populated area means there already were a lot of people who knew someone with cancer.

Best CR decision I've made today so far XD

chesstitans · Answer

boiled down to B and D.
C is wrong because it makes the situation more complex.
D is out b/c of "some" and D does not relate anything to people who know cancer patients.

sunny91 · Answer

Hi sayantanc2k,  Nevernevergiveup ,

I understood why other options are incorrect. I marked C as OA and understood why C is wrong. But, in B from 1990-2010, within this 20 years the cancer incidents increased by 40%. In 1990, nearly 80% of people in the United States reported that they knew someone who had been diagnosed with cancer. So, in a IN A DENSELY POPULATED URBAN CENTER MAY BE A LOT OF PEOPLE KNOWS EACH OTHER, BUT SINCE THE CANCER INCIDENTS INCREASED BY 40%, HOW CAN WE SAY THAT PEOPLE KNOW THE NEW CASES AS WELL, WHO ARE Diagnosed WITH CANCER. Since 80% of the US people know people who are diagnosed with cancer is constant since 1990, then even when the the cancer incidents increased, how come the percentage ie. 80 % people know people who are diagnosed with cancer? Kindly help me to understand.

P@PU · Answer

Clearly the option B. Easy reasoning. Was confused whether if there was any underlying twist i was missing, but POE helped to overcome it.

Mohammad Ali Khan · Answer

Here why are we not assuming that if no.of cases increase in city then the percentage of people knowing cancer patients would also go up.??..please guide.

ravi750 · Answer

this is too easy for a 700 level qs

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In 1990, nearly 80% of people in the United States reported

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In 1990, nearly 80% of people in the United States reported

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