Pavel made a list of 31 chores he needed to complete over the next 7 days. On the first 5...
GMAT Two Part Analysis : (TPA) Questions
Pavel made a list of 31 chores he needed to complete over the next 7 days. On the first 5 days, he completed 3, 5, 7, 2, and 6 of the listed chores, respectively. On the next 2 days, he completed the remaining 8 chores.
Select for Least possible median and for Greatest possible median values that are consistent with the information provided and give the least and greatest possible values, respectively, for the median of the numbers of the listed chores Pavel completed on each of the 7 days.
Phase 1: Owning the Dataset
Let's visualize this problem to make it crystal clear...
Timeline of Pavel's Chores:
Day: 1 2 3 4 5 6 7 Chores: 3 5 7 2 6 ? ? └─Total: 8─┘
We know:
- Days 1-5: Completed 3, 5, 7, 2, and 6 chores respectively
- Days 6-7: Completed remaining 8 chores total (but split unknown)
- Total verification: \(3 + 5 + 7 + 2 + 6 + 8 = 31\) ✓
Phase 2: Understanding the Question
We need to find the least and greatest possible medians for the 7 daily values.
For the median of 7 numbers:
- We arrange all values in order
- The median is the 4th value (middle of 7)
Current known values in order: 2, 3, 5, 6, 7
Key insight: Days 6 and 7 must add to 8, but we can choose how to split these 8 chores.
Phase 3: Finding the Answer
Possible ways to split 8 chores between days 6 and 7:
- \(0 + 8 = 8\)
- \(1 + 7 = 8\)
- \(2 + 6 = 8\)
- \(3 + 5 = 8\)
- \(4 + 4 = 8\)
- \(6 + 2 = 8\)
- \(7 + 1 = 8\)
- \(8 + 0 = 8\)
Let's check key scenarios:
For 4 + 4 split:
All values: 2, 3, 4, 4, 5, 6, 7
Median (4th value) = 4
For 0 + 8 split:
All values: 0, 2, 3, 5, 6, 7, 8
Median (4th value) = 5
For 3 + 5 split:
All values: 2, 3, 3, 5, 5, 6, 7
Median (4th value) = 5
Testing reveals: Only the (4,4) split gives median = 4. All other splits give median = 5.
Phase 4: Solution
Final Answer:
- Least possible median: 4 (when days 6 and 7 each have 4 chores)
- Greatest possible median: 5 (for all other valid splits)