sa18 wrote:

Hi

Why cannot A be the answer?

My explanation for A:

The passage says The incidence rates for both arthritis and high blood pressure increase with age.....The average age of the United States population will increase between 1987 and 2000.

if the average age is expected to increase and we know that incidence rate for arthritis and high BP increase with age, we can say that incident rate for these two problems has reduced => Sinusitis will be more common.

Check the question stem once again -

**Quote:**

In 1987 sinusitis was the most common chronic medical condition in the United States, followed by arthritis and high blood pressure, in that order.

1. Sinusitis {Remains same with age }

2. Arthritis {Increases with age}

3. Blood Sugar {Increases with age}Further it is given

**Quote:**

The average age of the United States population will increase between 1987 and 2000.

Consider simple numbers for the same

Let there be 2 people , age of the 2 people be 10 and 30

Average age of the 2 people in year 1 is = 20

Now consider their age after 10 years (considering there is no change in population ) , total age of the 2 people be 20 and 40

Average age of the 2 people in year 2 { after 10 years } is = 30

Since the probability of a person suffering from Sinusitis remains same irrespective of age , thus it will be same and it increases from 20 years in year 1 to 40 years in year 2

Further it is given that -

**Quote:**

The incidence rates for both arthritis and high blood pressure increase with age

Suppose the incidence rates for both arthritis and high blood pressure be 10% of the entire population in year 1 ,

According to the problem the incidence rates for both arthritis and high blood pressure will be 15% of the entire population in year 2The above 2 statement simply demonstrates the increase in rate in incidence rates for both arthritis and high blood pressure with age and you can not simply claim that Sinusitis is more common than arthritis and high blood pressure
_________________

Thanks and Regards

Abhishek....

PLEASE FOLLOW THE RULES FOR POSTING IN QA AND VA FORUM AND USE SEARCH FUNCTION BEFORE POSTING NEW QUESTIONS

How to use Search Function in GMAT Club | Rules for Posting in QA forum | Writing Mathematical Formulas |Rules for Posting in VA forum | Request Expert's Reply ( VA Forum Only )