In Patton City, days are categorized as having heavy rainfall (more th

Here is very good explanation https://www.gmatclub.com/forum/veritas-prep-resource-links-no-longer-available-399979.html#/2013/0 ... -the-gmat/

B , C and E can be eliminated easily as they contradict the facts in stem. Choice D can't be true , If we pay attention to the stem. Moderate rainfall is > 1 and <= 2 . So 2 times of 1.00001 will be 2.00002 , which is more than 2 inch. Hence , by the information in stem this choice can't be true and is incorrect.

Option A can be true assuming certain conditions.

I would request Gmat ninja and veritas prep to help explain the question and OA, I am thinking that the number of days with heavy rainfall should be more in 1990 than in 1990, but OA is the exact opposite

Yes, a higher number of days with heavy rainfall in 1990 is certainly possible and would, in fact, be the simplest solution. But it's not the only possibility.

The key to this question is to realize that each category represents a range of rainfall amounts. For example, we know that in 1990 there were fewer days with moderate rainfall than in 1910. But moderate means 1-2 inches. Even though the number of moderate days was higher in 1910, we don't know whether the total rainfall during those moderate days were closer to 1 inch or closer to 2 inches.

Perhaps most of the moderate days in 1990 were closer to 2 inches and most of the moderate days in 1910 were closer to 1 inch. In that case, it would certainly be possible for the total rainfall on moderate days in 1990 to be HIGHER than the total rainfall on moderate days in 1910, even though the number of moderate days was higher in 1910.

Similarly, the number of heavy days in 1910 could have been higher, but the total rainfall during those "heavy" days may have been barely higher than 2 inches on average. On the other hand, 1990 might have seen fewer heavy days, but the total rainfall during each of those heavy days could have been massive. Thus, the total rainfall in 1990 could have easily been higher even if the number of days within each category was lower.

So while it is certainly possible that there were more heavy days in 1990, this does not HAVE to be true.

I hope that helps!
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it is given that the days of LR and MR, but didn't give the day of no rain.
and there's an situation:the rainfall of heavy rain is very large, and NO rain days in 90 are more than in 10, so B and C are possible?

How come the number oof days with heavy rainfall was lower in 1990 than in 1910 if the total rainfall was higher? Considering there were also fewer days with light and moderate rainfall...

I applied the elimination process with the help of mathematical representation and left with A as others are not possible

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Option A is correct.

Suppose there were 0 days with no rainfall.

Rainfall 1990 1910
Heavy >2 Z1 =365-(X1+Y1) Z2=365-(X2+21)
Moderate 1-2 X1 X2
Low 0-1 Y1 Y2

It is given that X1>X2 and Y1>Y2. This proves Z1<Z2. Thus, option A can be one of the possibilities.

Option A is correct.

Suppose there were 0 days with no rainfall.

Rainfall 1990 1910
Heavy >2 Z1 =365-(X1+Y1) Z2=365-(X2+21)
Moderate 1-2 X1 X2
Low 0-1 Y1 Y2

It is given that X1>X2 and Y1>Y2. This proves Z1<Z2. Thus, option A can be one of the possibilities.

Hi VeritasKarishma,
While evaluating option D, why isn't number of hours rained per day not considered. Can we not take this assumption into consideration?

Kindly help me with this query.

Thanks,
Siva.

You can image some extreme situations that result in A: the H day in 1990.eg. One day rain 20 meters....

can you please explain why we are not considering no rainfall case??