Confusing Inference Question (Manhattan)....Expert needed

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Recent studies show that people between the ages of 13 and 55 produce 65 pounds more garbage per year than they did in 1995. This increase has led to a higher percentage of the total garbage produced by all the age groups. This age group constitutes a growing percentage of the population, so it partially explains this rise.

Which of the following can be concluded from passage?

A. People over the age of 55 produce more garbage than people less than the age of 13.
B. Population has risen since 1995.
C. People between the age of 13 and 55 are more than half of current population.
D. Before 1995, people below age 13 and above age 55 produced higher percentage of total garbage than they do now.
E. People between the age of 13 and 55 produce more garbage than those below 13 or older than 55.

OA: D

Source: Manhattan

[spoiler]In Choice D, it mentioned 'before 1995' but actually we do not anything before 1995 (i.e in 1994,1993....etc). We just know about now and exactly what happened in 1995. How come it is the correct answer?[/spoiler]

Thanks in advance for help

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by GMATGuruNY » Fri Mar 17, 2017 10:55 am
Mo2men wrote:In Choice D, it mentioned 'before 1995' but actually we do not anything before 1995 (i.e in 1994,1993....etc).
From the New York Times:
Live Nation currently produces more than 26,000 live events per year.
Here, the phrase in blue implies the following statistic:
(total number of events)/(total number of years) > 26,000.
The only way to calculate this statistic is to count the total number of events produced OVER THE PAST FEW YEARS.
Thus, despite the usage of the word currently, the statement from the NY Times implies that -- over the past few years -- the average number of events per year has been greater than 26,000.

People between the ages of 13 and 55 produce 65 pounds more garbage per year than they did in 1995.
The statement above seems to make the following comparison:
People between the ages of 13 and 55 produce 65 pounds more garbage per year now than they produced per year in 1995.
Here, the only way to calculate the statistic in red is to count the amount of garbage produced in the years PRECEDING 1995.
Thus, the passage implies that -- in the years leading up to 1995 -- the average amount of garbage produced each year was less than that currently produced each year.
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by Mo2men » Fri Mar 17, 2017 11:01 am
GMATGuruNY wrote:
Mo2men wrote:In Choice D, it mentioned 'before 1995' but actually we do not anything before 1995 (i.e in 1994,1993....etc).
From the New York Times:
Live Nation currently produces more than 26,000 live events per year.
Here, the phrase in blue implies the following statistic:
(total number of events)/(total number of years) > 26,000.
The only way to calculate this statistic is to count the total number of events produced OVER THE PAST FEW YEARS.
Thus, despite the usage of the word currently, the statement from the NY Times implies that -- over the past few years -- the average number of events per year has been greater than 26,000.

People between the ages of 13 and 55 produce 65 pounds more garbage per year than they did in 1995.
The statement above seems to make the following comparison:
People between the ages of 13 and 55 produce 65 pounds more garbage per year now than they produced per year in 1995.
Here, the only way to calculate the statistic in red is to count the amount of garbage produced in the years PRECEDING 1995.
Thus, the passage implies that -- in the years leading up to 1995 -- the average amount of garbage produced each year was less than that currently produced each year.
Superb explanation.

Thanks Mitch

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by othman24 » Sat Apr 15, 2017 3:55 pm
I don't want to disagree with explanation above but I honestly still cannot assimilate the provided explanation.

The reason is the following: The answer must be true.
Answer D gives us that Before 1995, (I do agree with calculation and how to relate to that period) but D give us the people below 13 and above 55 produced higher percentage of total garbage before 1995 than they do now. On the other hand, in the stimulus, it is said "This increase has led to a higher percentage of the total garbage produced by all the age groups". Which means that all age groups have produced more than they did before 1995. Therefore, it contradicts with the question being asked.

I honestly picked E where it can be concludud that the group age (13, 55) are a growing percentage compared to all age group and can be inferred that they produce more garbage than the outer groupe age )13, 55(.

Thanks,

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by GMATGuruNY » Sun Apr 16, 2017 2:48 am
othman24 wrote:On the other hand, in the stimulus, it is said "This increase has led to a higher percentage of the total garbage produced by all the age groups". Which means that all age groups have produced more than they did before 1995. Therefore, it contradicts with the question being asked.
Recent studies show that people between the ages of 13 and 55 produce 65 pounds more garbage per year than they did in 1995. This increase has led to a higher percentage of the total garbage produced by all the age groups.
Conveyed meaning:
Of the total garbage currently being produced, the percentage produced by people between the ages of 13 and 55 has INCREASED, implying that the percentage produced by everyone else -- people NOT between the ages of 13 and 55 -- has DECREASED.
It is not possible for BOTH groups to produce a higher percentage of the total amount of garbage.
Since people between the ages of 13 and 55 are producing a HIGHER percentage of the garbage, the remaining people must be producing a LOWER percentage of the garbage.
I honestly picked E where it can be concludud that the group age (13, 55) are a growing percentage compared to all age group and can be inferred that they produce more garbage than the outer groupe age )13, 55(.

Thanks,
E. People between the age of 13 and 55 produce more garbage than those below 13 or older than 55.
Consider the following case:
In 1995, people between the ages of 13 and 55 produced 10% of the total garbage, while the remaining people produced 90% of the total garbage.
Now, people between the ages of 13 and 55 produce 20% of the total garbage, while the remaining people produce 80% of the total garbage.
In this case, option E is not true.
Eliminate E.
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I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
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