In 2000, the Agronomy Research Lab at Andes Valley University initiated a decade-long study to enhance the productivity of quinoa, a crop indigenous to South America known for its resilience and high nutritional value. The study was motivated by analysis of historical data from 1980 to 2000, which showed a consistent decline in annual rainfall across the region and a corresponding reduction in quinoa yield per hectare. https://gmatclub.com/forum/download/file.php?id=84503Researchers hypothesized that declining rainfall was a key limiting factor in crop productivity. To counter this, they explored two lines of experimental intervention: Experiment 1 (2001–2010): Testing three newly formulated pesticides—A, B, and C—applied independently. These were developed to reduce pest-induced losses, which tend to rise during drier conditions. https://gmatclub.com/forum/download/file.php?id=84504 Each intervention was tested under controlled conditions on plots of comparable soil quality and sunlight exposure. Yield was measured annually in kilograms per hectare. The graphs show different starting yields for each treatment due to natural variation in soil quality, microclimate, or other localized experimental conditions.Experiment 2 (2001–2010): Applying the same pesticides in combination with a nitrogen-rich fertilizer, to assess whether nutrient supplementation could amplify the effect of pest control and offset yield losses due to environmental stress. https://gmatclub.com/forum/download/file.php?id=84505 Each intervention was tested under controlled conditions on plots of comparable soil quality and sunlight exposure. Yield was measured annually in kilograms per hectare. The graphs show different starting yields for each treatment due to natural variation in soil quality, microclimate, or other localized experimental conditions. GMAT-Club-Forum-7xdpa8ba.png GMAT-Club-Forum-d08xfm8f.png GMAT-Club-Forum-vkytggfw.png

Solution: Q1: Between 2001 and 2010, which of the following experiments saw the greatest percentage increase in yield? Answer: Fertilizer + Pesticide C Explanation: The graph shows that Fertilizer + Pesticide C started around 1270 kg/ha and rose to about 1430 kg/ha—an increase of roughly 160 kg/ha. This is a larger absolute and percentage increase than any other listed treatment, including Pesticide C alone. Visually, its slope is the steepest, indicating the highest growth rate. Q2: For each pair below, determine whether the fertilizer + pesticide combination resulted in a larger total increase in yield from 2000 to 2003 than the corresponding pesticide used alone. Answers: Pesticide A — No Pesticide B — No Pesticide C — Yes Explanation: From the graph: Fertilizer + Pesticide A shows a yield decline over this period, while Pesticide A increases slightly. Fertilizer + Pesticide B is almost stable over this period, but Pesticide B’s increase is greater. Fertilizer + Pesticide C shows a much steeper rise than Pesticide C alone. Only the Fertilizer + C combination produces a larger gain than its pesticide-only counterpart. Q3: In agricultural policy, water productivity is defined as: Water Productivity = Yield (kg/hectare) ÷ Rainfall (mm). Which of the following is closest to the percentage change in water productivity from 1980 to 2000? Answer: +20% Explanation: Approximate values from the graph: 1980: Yield ≈ 1100, Rainfall ≈ 800 ⇒ WP ≈ 1.375 2000: Yield ≈ 1000, Rainfall ≈ 600 ⇒ WP ≈ 1.667 Percentage change: (1.667 − 1.375) ÷ 1.375 ≈ 0.21 or 21% increase. Closest listed value: +20%

In 2000, the Agronomy Research Lab at Andes Valley University initiate : Multi-Source Reasoning (MSR)

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Aaah yes, how did I overlook that, thanks for the clarification !

catinabox

Are you looking at the right time frame from the graph? The question asks for the results from 2000 to 2003 only.

Saksham23

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For each pair below, determine whether the fertilizer + pesticide combination resulted in a larger total increase in yield from 2000 to 2003 than the corresponding pesticide used alone.

Select “Yes” if the fertilizer + pesticide combination produced a larger yield gain during that period.
Select “No” if the pesticide-alone treatment had equal or greater yield gain.

Why is pesticide A + fertilizer answer as no ? From the graph, the line seems to be above whatever we have for the counterpart only pesticide ?

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19 Jun 2025, 15:27

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The Yield in Declining in 2003 for pesticide A + Fertiliser

Saksham23

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Why is pesticide A + fertilizer answer as no ? From the graph, the line seems to be above whatever we have for the counterpart only pesticide ?

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Can anyone provide me the solution for Q3

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Read through all the tabs patiently, and gather all imp key details. Here are mine,

Historical Yield and Rainfall

We are given a chart which shows how rainfall and yield of quinoa has decreased from 1980 to 2000. Units of x axis is year, and y axis is mm and kg/hectare. Blue solid line is rainfall and black dotted line is yield. Study and research started in 2000.

Pesticide-only Experiment

Only pesticides of 3 different varieties are used - A (blue solid line), B (black dotted line), C (orange dotted line). This graph starts from 2001, which might imply that the pesticides were used in 2000 for the first time, and the results are being observed after an year. Note the units of x and y axis. At a high level, all these lines are having an estimate of 70-120 kg/hectare increase where C is leading the pack whereas B is trailing.

Fertilizer + Pesticide Experiment

Now pesticides + fertilizers are used for all three of them - A (blue solid line), B (black dotted line), C (orange dotted line). Units are same as in the previous tab. Graph for C is rushing to the roof with close to 150 points increase whereas B has just no care in the world as it's showing no progress over time.

1. Between 2001 and 2010, which of the following experiments saw the greatest percentage increase in yield?

Straightforward after the analysis, Fertilizer + Pesticide C

2. For each pair below, determine whether the fertilizer + pesticide combination resulted in a larger total increase in yield from 2000 to 2003 than the corresponding pesticide used alone.
To calculate the yield increase, use the difference between the starting and ending yield of each treatment as shown in its respective graph.

Select “Yes” if the fertilizer + pesticide combination produced a larger yield gain during that period.
Select “No” if the pesticide-alone treatment had equal or greater yield gain.

Yes	No
	No	Pesticide A + Fertilizer
	No	Pesticide B + Fertilizer
Yes		Pesticide C + Fertilizer

C and B should be straightforward after our initial read. As C showed considerable increase, while B tanked badly with fertilizer, I would have a rough estimate of what would have happened there.

Pesticide A => ~10
Pesticide A + Fertilizer => ~-10

Pesticide B => ~20
Pesticide B + Fertilizer => ~0

Pesticide C => ~20
Pesticide C + Fertilizer => ~50

3. In agricultural policy, water productivity is defined as: Water Productivity = Yield (kg/hectare) ÷ Rainfall (mm).

Which of the following is closest to the percentage change in water productivity from 1980 to 2000?

Let's go to the first tab,

Water Productivity in 1980 = Yield in 1980/ Rainfall in 1980 = 1100/800 = 1.375
Water Productivity in 2000 = 1000/600 = 1.65

Increase = 0.275/1.375 = 20%

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Solution:

Q1: Between 2001 and 2010, which of the following experiments saw the greatest percentage increase in yield?
Answer: Fertilizer + Pesticide C
Explanation:
The graph shows that Fertilizer + Pesticide C started around 1270 kg/ha and rose to about 1430 kg/ha—an increase of roughly 160 kg/ha. This is a larger absolute and percentage increase than any other listed treatment, including Pesticide C alone. Visually, its slope is the steepest, indicating the highest growth rate.

Q2: For each pair below, determine whether the fertilizer + pesticide combination resulted in a larger total increase in yield from 2000 to 2003 than the corresponding pesticide used alone.
Answers:
Pesticide A — No
Pesticide B — No
Pesticide C — Yes
Explanation:
From the graph:

Fertilizer + Pesticide A shows a yield decline over this period, while Pesticide A increases slightly.
Fertilizer + Pesticide B is almost stable over this period, but Pesticide B’s increase is greater.
Fertilizer + Pesticide C shows a much steeper rise than Pesticide C alone.

Only the Fertilizer + C combination produces a larger gain than its pesticide-only counterpart.

Q3: In agricultural policy, water productivity is defined as: Water Productivity = Yield (kg/hectare) ÷ Rainfall (mm).
Which of the following is closest to the percentage change in water productivity from 1980 to 2000?
Answer: +20%
Explanation:
Approximate values from the graph:

1980: Yield ≈ 1100, Rainfall ≈ 800 ⇒ WP ≈ 1.375
2000: Yield ≈ 1000, Rainfall ≈ 600 ⇒ WP ≈ 1.667

Percentage change:
(1.667 − 1.375) ÷ 1.375 ≈ 0.21 or 21% increase.
Closest listed value: +20%

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Hi experts MartyMurray KarishmaB

I need your two cents on the MSR approach, I tried a new approach with this set by going to questions directly and realised that it saved my time significantly by not starting with reading passage and was able to find data for questions easily. Is this a good strategy for MSRs or I should absorb the data first at least at a high level? I think reading passage first is good for Non-Math MSRs which are more like RCs.

I would appreciate your thoughts.