The graph shows three data sets from a 5-day weather forecast for a

Question

https://gmatclub.com/forum/download/file.php?mode=view&id=74127 The graph shows three data sets from a 5-day weather forecast for a certain city—one set each for daily average air pressure, daily high and low temperatures, and daily average percentage of cloud cover. Select the options from the drop-down menus that complete the statement so that it most accurately reflects the information provided. Among the three data sets shown in the graphs, the values for GRAPH_1_PLACEHOLDER would be most strongly negatively correlated with a data set consisting of the 5 GRAPH_2_PLACEHOLDER of the daily values shown for temperature. 2.jpg DI - 5.png https://gmatclub.com/forum/download/file.php?id=81474 GMAT-Club-Forum-2nzjr302.png

chetan2u · Accepted Answer

You are correct with your observation. Both Maximum and Range are increasing with decrease in cloud cover, and here comes into play, the words ‘most strongly correlated’.

The maximum temperature is increasing, while the minimum temperature is decreasing, so the Range is increasing by more margin and thus most strongly correlated

T4Star · Answer

Nice question.

First, we look at the second drop down.

If we look at the graph of the temperature closely, we see that the difference in the min and max temperature is rising daily. In other words, the range of temperature is rising.

Simultaneously the % of cloud cover has decreasing trend indicating a negative correlation with temperature range.

So 1st ans: daily average % of cloud cover
2nd ans: ranges

ArjunKumar25 · Answer

Why is Cloud cover wrong as an answer

chetan2u · Answer

Cloud cover is the correct answer.

What is the query?

ROY13 · Answer

Can someone please explain why the 2nd answer is range; the maximums are also increasing just like the range (as the minimums are also slightly decreasing). So, why the negative correlation is only between cloud coverage and range and not cloud coverage and maximum temp?

elele · Answer

In the version of the official mock I took recently, they must have changed the options for the second dropdown (instead of "maximums" there is a "means" option) probably to avoid any confusion.

GMATinsight · Answer

You are absolutely correct Roy.

The maximums are negatively correlated and the correlation of the maximum may not be easily compared with the correlation of ranges hence in my opinion both asnwers would be correct.

It's strange to see such an official questions which may have two possible answers.

PReciSioN · Answer

The actual options from the mock contain 'Mean' instead of maximum which is not increasing. https://gmatclub.com/forum/download/file.php?id=82835 GMAT-Club-Forum-x80toe76.png

Bunuel · Answer

Fixed the options. Thank you! GMAT-Club-Forum-gw949t9i.png

imslogic · Answer

Why is the answer cloud cover and not air pressure? Air pressure increases when the range is flat for the first 3 days and then decreases for the 4th and 5th days while cloud cover stays flat with the range for the first 3 days and then decreases for the 4th and 5th.

GauriAkode22 · Answer

Let’s start with the second drop down for daily value for temperature. We have 3 options - means, minimums and ranges. 
The mean - we don’t have values to calculate 
The minimums - it is showing decrease over days
The range - It is increase over days

So for negative correlation with the minimum temperature we need a graph showing a positive increase with days which we don’t have

For negative correlation with the ranges, we need a graph showing decrease with days which is shown in percentage of cloud cover

KarishmaB · Answer

Among the three data sets shown in the graphs, the values for ____________ would be most strongly negatively correlated with a data set consisting of the 5 ________ of the daily values shown for temperature.

What do we start with here? The first blank has the three graphs as an option. The second blank focuses on 3 stats of the temperature graph. We can find these stats so we need to focus on that first.

The temperature graph for each day gives us minimum and maximum temperature points only. So this is what we can say about the 3 stats:

Mean  - Min and Max values do not give us any indication of value of mean. Not possible to find.
 Min temp  - The minimum temperature is steadily reducing over the 5 days.
 Range  - The minimum temperature is reducing over the 5 days and the maximum temperature is increasing over the 5 days so range is steadily increasing over the 5 days.

We need a stat that is negatively correlated with something else. The cloud cover % is steadily reducing. We saw that the range of temp is steadily increasing. This is a great negative correlation.

Select  cloud cover  and  ranges

Nsp10 · Answer

can't we say the sum of (max temp+min temp)/2 as mean or avg temp per day ?
{ though still since both min value is decreasing and max is increasing it will mostly be constant throughout }

cheshire · Answer

you can approximate it like that but you will see almost no correlation with cloud cover (as the average won't vary much), which is what the problem is asking for.

egmat · Answer

Understanding What We're Looking For

First, let's clarify what "negatively correlated" means – when one variable goes up, the other goes down. You need to find which weather variable (air pressure or cloud cover) moves in the opposite direction from some aspect of temperature.

Step 1: Analyze the Trends

Looking at the graphs, notice these patterns:
-  Air pressure : Forms a peak at Day 3 (rises then falls)
-  Temperature : Shows a zigzag pattern between highs (~20°C) and lows (~10°C)
-  Cloud cover : Steadily decreases from nearly 100% to below 50%

Step 2: Identify the Key Relationship

Here's what you need to see: Cloud cover shows the most consistent trend – it's continuously decreasing. Now think about what aspect of temperature could increase as cloud cover decreases.

Notice how temperature alternates between highs and lows each day? The  difference  between these values – the daily temperature  range  – is what we should focus on.

Step 3: Apply Weather Logic

This is where it clicks! When there's less cloud cover (clearer skies):
- Days get hotter (more direct sunlight)
- Nights get cooler (heat escapes more easily)
- Therefore, the temperature  range  increases

As cloud cover steadily decreases over the 5 days, the temperature ranges would increase – that's a  negative correlation !

Answer:  
Blank 1:  daily average percentage of cloud cover 
Blank 2:  ranges

You can check out the  step-by-step solution on Neuron by e-GMAT  to master the systematic framework for tackling correlation questions across different Data Insights scenarios. You'll also discover how to quickly identify patterns in multi-variable graphs and learn the time-saving techniques for similar weather-data problems. Feel free to explore other GMAT official questions with detailed solutions on Neuron for structured practice  here .

nihilre · Answer

There is no option for Maximum..

The graph shows three data sets from a 5-day weather forecast for a

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