Solution
5 teams 15 members (in each team) 75 total members.
Equal distribution across skill sets 25 biologists, 25 geologists, 25 explorers.
Step 1. Create your data-structure (table). If this is properly done, half of the headache is solved:
| Team | Biologists | Geologists | Explorers | Total |
|---|---|---|---|---|
| A | 15 | |||
| B | 15 | |||
| C | 15 | |||
| D | 15 | |||
| E | 15 | |||
| Total | 25 | 25 | 25 | 75 |
Step 2. From “Teams C and D have 6 biologists each, Team A has 6 geologists” (point 2):
| Team | Biologists | Geologists | Explorers |
|---|---|---|---|
| A | 6 | ||
| B | |||
| C | 6 | ||
| D | 6 | ||
| E |
Step 3. Explorers are all distinct, decreasing A → E, summing to 25 with each ≥2 (points 4 & 1).
The only fit is: .
Whenever points like these are mentioned, don't get lazy, just start adding
| Team | Biologists | Geologists | Explorers |
|---|---|---|---|
| A | 6 | 7 | |
| B | 6 | ||
| C | 6 | 5 | |
| D | 6 | 4 | |
| E | 3 |
Step 4. Now each team total is 15. Find the remaining value for A, C and D:
| Team | Biologists | Geologists | Explorers |
|---|---|---|---|
| A | 2 | 6 | 7 |
| B | 6 | ||
| C | 6 | 4 | 5 |
| D | 6 | 5 | 4 |
| E | 3 |
Step 5. For B, we need (point 3) and (point 1).
So, biologists need to be 7 or more:
- If we have 7 biologists, we can have 2 geologists ✅
- If we have 8 biologists, we can have only 1 geologist ❌ -> At least 2 are required (point 1).
| Team | Biologists | Geologists | Explorers |
|---|---|---|---|
| A | 2 | 6 | 7 |
| B | 7 | 2 | 6 |
| C | 6 | 4 | 5 |
| D | 6 | 5 | 4 |
| E | 3 |
Step 6. Finally, for E, every column (biologists, geologists, explorers must sum to 25):
| Team | Biologists | Geologists | Explorers |
|---|---|---|---|
| A | 2 | 6 | 7 |
| B | 7 | 2 | 6 |
| C | 6 | 4 | 5 |
| D | 6 | 5 | 4 |
| E | 4 | 8 | 3 |
Only teams A and E have more geologists than biologists, hence, answer is 2.