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GMAT695
Joined: 12 Jul 2023
Last visit: 19 Dec 2025
Posts: 544
Given Kudos: 243
Location: India
Concentration: Entrepreneurship, Finance
Schools: Stern '27 Fuqua '27 Columbia '27
GMAT Focus 1: 535 Q77 V78 DI74 
GMAT Focus 2: 575 Q83 V74 DI78
GMAT Focus 3: 635 Q87 V81 DI76
GMAT 1: 420 Q31 V17
GPA: 7.37
WE:Business Development (Finance)
28 Sep 2024, 04:17
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Dropdown 1: 1
Dropdown 2: 3
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
55%
(hard)
Question Stats:
69% (02:36) correct
31%
(02:41)
wrong
based on 1350
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Psychologists interested in classroom behaviors recently conducted a study in which four groups of students—Groups A through D—were recorded for several minutes while completing a series of puzzles. In reviewing the recording, the psychologists noted a number of occurrences of what they characterize as cooperative behaviors along with the time that each behavior was observed. The graph shows the distribution of these observations in the four groups of students, as well as the total number of occurrences of cooperative behaviors for each group. For instance, the graph shows that for Group A, exactly 1 occurrence of a cooperative behavior was observed within the first 10 seconds and exactly 4 were observed within the first 30 seconds.
Select from each drop-down menu the option that creates the most accurate statement, based on the information provided.
For exactly of the 4 groups, the majority of the occurrences of cooperative behaviors were observed within the first 50 seconds of the observation.
For exactly of the 4 groups, the number of occurrences of cooperative behaviors within the first 50 seconds was greater than 15.
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28 Sep 2024, 09:16
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Here, accumulated number of occurrences has been considered.
1. Considering Group B, within 50 seconds total number of occurrences outweighs the total number of occurrences in Group B. Therefore, only Group B must be selected. Rest of the groups can't fulfill the criteria.
2. If we add or simply observe the pattern of number of occurrences in Group B, C and D, we can find out that within 50 seconds total number of occurrences in each group exceeds 15. So, answer is 3
1. Considering Group B, within 50 seconds total number of occurrences outweighs the total number of occurrences in Group B. Therefore, only Group B must be selected. Rest of the groups can't fulfill the criteria.
2. If we add or simply observe the pattern of number of occurrences in Group B, C and D, we can find out that within 50 seconds total number of occurrences in each group exceeds 15. So, answer is 3
29 Sep 2024, 11:23
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1. The question is consisted of 2 parts. Part 1 asks us for the number of groups such that "the majority of the occurrences of cooperative behaviors were observed within the first 50 seconds of the observation". Part 2 asks us for the number of groups such that "the number of occurrences of cooperative behaviors within the first 50 seconds was greater than 15".
2. Part 1. Counting the number of observations in each group would waste too much time. So, we can estimate by looking at the area beneath 50 seconds and above.
- Group A. The area beneath 50 seconds is about \(\frac{1}{3}\) of the total area. \(\frac{1}{3} \leq \frac{1}{2}\), so it's not the majority.
- Group B. The area beneath 50 seconds looks more than \(\frac{1}{2}\) of the total area. So, the majority is under 50 seconds.
- Group C. Here, the area beneath 50 seconds is a little bit more than \(\frac{1}{3}\) of the total area, however, it's definitely less than \(\frac{1}{2}\) of the total area. So, it's not the majority.
- Group D. The area beneath 50 seconds is less than the area in 100 - 150 seconds. So, it's not the majority.
3. Part 2. Here we can estimate too but sometimes we might have to count.
- Group A. This is too close to say, so we calculate it: 1 + 1 + 2 + 1 + 6 = 11 \(\leq\) 15. So, this group doesn't count.
- Group B. There are two bars that are at least 12 each: Area \(\geq 12 * 2 = 24 > 15\). So, this group does count.
- Group C. We have 1 bar that's at least 12 and 3 that are at least 4 each: Area \(\geq 12 + 4 * 3 = 24 > 15\). So, this group does count.
- Group D. We have 2 bars with at least 8 each: Area \(\geq 8 * 2 = 16 > 15\). So, this group does count.
4. That means our answer is Part 1 - 1 group and Part 2 - 3 groups.
2. Part 1. Counting the number of observations in each group would waste too much time. So, we can estimate by looking at the area beneath 50 seconds and above.
- Group A. The area beneath 50 seconds is about \(\frac{1}{3}\) of the total area. \(\frac{1}{3} \leq \frac{1}{2}\), so it's not the majority.
- Group B. The area beneath 50 seconds looks more than \(\frac{1}{2}\) of the total area. So, the majority is under 50 seconds.
- Group C. Here, the area beneath 50 seconds is a little bit more than \(\frac{1}{3}\) of the total area, however, it's definitely less than \(\frac{1}{2}\) of the total area. So, it's not the majority.
- Group D. The area beneath 50 seconds is less than the area in 100 - 150 seconds. So, it's not the majority.
3. Part 2. Here we can estimate too but sometimes we might have to count.
- Group A. This is too close to say, so we calculate it: 1 + 1 + 2 + 1 + 6 = 11 \(\leq\) 15. So, this group doesn't count.
- Group B. There are two bars that are at least 12 each: Area \(\geq 12 * 2 = 24 > 15\). So, this group does count.
- Group C. We have 1 bar that's at least 12 and 3 that are at least 4 each: Area \(\geq 12 + 4 * 3 = 24 > 15\). So, this group does count.
- Group D. We have 2 bars with at least 8 each: Area \(\geq 8 * 2 = 16 > 15\). So, this group does count.
4. That means our answer is Part 1 - 1 group and Part 2 - 3 groups.
