Last year the domestic consumption of freshwater water collected

Question

Last year the domestic consumption of freshwater, water collected directly from water sources such as rivers and ponds, in Aquaville was twice that of recycled water, used water that has been purified and treated artificially. An analyst has projected that by 2015, the city will use at least as much recycled water annually as it does freshwater, while using a greater quantity of freshwater than it did last year.

If the information above is correct and the analyst’s projections prove to be accurate, which of the following projections must also be accurate?

(A) Aquaville will consume less water in 2015 than it did last year 
(B) In 2015, Aquaville will use at least twice as much water, in total, as it did last year.
(C) As compared with last year, in 2015, Aquaville will consume less recycled water. 
(D) In 2015, Aquaville will consume more water from a given supply of water than it did last year. 
(E) In 2015, Aquaville will use at least twice as much recycled water as it did last year

NimishaKrishna · Answer

Confused on choosing between D and E. Can someone please clarify

gmatcore16 · Answer

So I also chose D over E, but then realised my mistake.

So let's take some simple numbers to understand this:
Last year: 
water consumption from recycled water = 1
Water consumption from freshwater sources was twice = 2

2015 projection: 
Recycled water consumption = freshwater consumption
and freshwater consumption in 2015 > freshwater consumption last year

Assuming freshwater consumption in 2015 is 2.1 (greater than last year), then recycled water consumption in 2015 is also 2.1

Hence, E.

minustark · Answer

Last year: Freshwater = 2/3, Refined water=1/3.
This year : Freshwater and refined water almost same. So, water consumption becomes ( 2/3 *2) or at least 4/3 of last year. It may not be doubled. But the refined water will be at least (1/3 - 2/3) = 1/3 much than last year,so the correct answer is E.

Priya8997 · Answer

I am still confused between options D and E. Can someone clarify why D won't be the right choice here?

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jcgomezlv · Answer

I am also confused.

Why D cannot be the right choice?

vinny12 · Answer

Let me try to explain this.

The argument says that right now let's say freshwater usage = 100 so recycled water = 50. Total water usage = 150.

As per the argument "the city will use at least as much recycled water annually as it does freshwater, while using a greater quantity of freshwater than it did last year." i.e.

the freshwater in 2015 > 100 and because the recycled water has to be at least as much as freshwater hence recycled water has to be >100, which is at least twice as much of recycled water usage last year.

Does this make sense?

jcgomezlv · Answer

I agree partially with your reasoning.

For me option E is incorrect because it says AT LEAST TWICE, which is not true. In the stimulus it clearly says that it will be MORE THAN TWICE.

(E) In 2015, Aquaville will use  at least twice  as much recycled water as it did last year

In other words, if freshwater in 2015 was 100 and recycled water was 50, the stimulus says that the freshwater will be  MORE THAN  100(could be 102) and the recycled water will be  EQUAL TO  the freshwater(102), which is  MORE THAN TWICE  the quantity of 2015.

But option D says: 
 "(D) In 2015, Aquaville will consume more water from a given supply of water than it did last year."  Which is true! in both kinds of supply the consumption will be more according to the stimulus:  An analyst has projected that by 2015, the city will use at least as much recycled water annually as it does freshwater, while using a greater quantity of freshwater than it did last year.

Hence, IMO option D is the correct answer.

Could you please double check?

"An analyst has projected that by 2015, the city will use at least as much recycled water annually as it does freshwater, while using a greater quantity of freshwater than it did last year."

vinny12 · Answer

The argument says that right now let's say freshwater usage = 100 so recycled water = 50. Total water usage = 150.

As per the argument "the city will use at least as much recycled water annually as it does freshwater, while using a greater quantity of freshwater than it did last year." i.e.

the freshwater in 2015 > 100 and because the recycled water has to be at least as much as freshwater hence recycled water has to be >100, which is at least twice as much of recycled water usage last year.

I agree partially with your reasoning.

For me option E is incorrect because it says AT LEAST TWICE, which is not true. In the stimulus it clearly says that it will be MORE THAN TWICE.

(E) In 2015, Aquaville will use  at least twice  as much recycled water as it did last year

In other words, if freshwater in 2015 was 100 and recycled water was 50, the stimulus says that the freshwater will be  MORE THAN  100(could be 102) and the recycled water will be  EQUAL TO  the freshwater(102), which is  MORE THAN TWICE  the quantity of 2015.

But option D says: 
 "(D) In 2015, Aquaville will consume more water from a given supply of water than it did last year."  Which is true! in both kinds of supply the consumption will be more according to the stimulus:  An analyst has projected that by 2015, the city will use at least as much recycled water annually as it does freshwater, while using a greater quantity of freshwater than it did last year.

Hence, IMO option D is the correct answer.

Could you please double check?

"An analyst has projected that by 2015, the city will use at least as much recycled water annually as it does freshwater, while using a greater quantity of freshwater than it did last year."

I agree with your reasoning here but the point you're missing in option D is that it says "In 2015, Aquaville will consume more water  from a given supply of water  than it did last year."

However this is sure that in 2015, Aquaville will consume more water than it did earlier but we can't be sure of the given supply of water part. That's the reason option D is wrong IMO.

I'd love to hear from an expert on this.

rishab0507 · Answer

Your mathematical reasoning for E is correct, But how can D be wrong, In both cases :freshwater and recycled water is used more than last year. No justification to eliminate D. Either option is not written correctly or its a bad Q type

Albymana · Answer

Shouldn’t E reads “more than twice”?

Last year : 1-2
2015: for freshwater being more than before, at least 2,0001. Thus Recycled must be MORE than doubled.... am I wrong?

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GMAToverPUBG · Answer

I chose  E over D  because mathematically, E will always be true, if the prediction comes true, and D sounds to be absolutely correct, BUT:

Because it says:

D) In 2015, Aquaville will  consume  more water from a given supply of water than it did last year. - The premise says that prediction is to  USE  and not  CONSUME 
E) In 2015, Aquaville will  use  at least twice as much recycled water as it did last year - This mentions use. so  Correct.

Although both sound the same but it can be different. Eg. - You consume water when you drink. You use water to cut metal.

Hence, E.

Pranjal3107 · Answer

is D wrong because of Consume and use ?

Mavisdu1017 · Answer

I just guess: 
D says “from a given supply of water”, but maybe there are other kinds of supplies except freshwater and recycled water, and passage just take these two kinds as examples. So D is wrong.

pavanhra · Answer

Option D gives talks about water and doesn't specify whether it is fresh water or used water whereas option E gives more clarity about the same.

also in stimulus it is said that fresh water is used twice of the used water. and in the projected 2015 years usage the used water will be as much as last years fresh water which means that the used water usage will be doubled

as this gives better clarity so option E is correct answer

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AbhishekP220108 · Answer

Can you please elaborate why D is wrong, I get it why E is correct but can you please provide apt reason to eliminate D? Is there any difference related to consume and use?

egmat · Answer

AbhishekP220108  The critical issue with option D is the phrase  "from a given supply of water."

Option D states: "In 2015, Aquaville will consume more water from a given supply of water than it did last year."

This phrase introduces an element that  is not addressed anywhere in the passage :
 
 Is the water supply fixed or limited? 
 What is the capacity of the water sources? 
 Are we measuring efficiency of extraction from a supply?

The passage only tells us about the  amounts  of freshwater and recycled water consumed. It provides:
 
 Last year: Freshwater  = 2 	imes  Recycled water 
  2015 : Recycled water  \geq  Freshwater AND Freshwater  >  Last year's freshwater

Nothing about supply capacity or the relationship between consumption and supply.

The Trap:  Option D sounds plausible because we can deduce that total consumption will increase. However, "from a given supply" makes an assumption about supply constraints that cannot be verified from the passage. On "must be true" inference questions, we can only conclude what  definitively follows  from the given information.

Hope this clears your doubt?

Last year the domestic consumption of freshwater water collected

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Last year the domestic consumption of freshwater water collected

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

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From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

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