This is a great counting problem that tests your ability to break down a word problem into clear categories. The key is carefully reading what each manager evaluates and then multiplying correctly.
Let me walk through the setup first:
We have 5 managers and 30 technicians total. Each manager supervises 6 technicians (since 5 managers × 6 technicians each = 30 total technicians). The question tells us that in April, each manager will evaluate two groups of people:
1. Each technician reporting to them
2. Each of the other managers
Step 1: Count evaluations of technicians
Each manager evaluates their own 6 technicians.
Since there are 5 managers, that's 5 × 6 = 30 technician evaluations.
Step 2: Count evaluations of other managers
Each manager evaluates "each of the other managers." If there are 5 managers total, then "the other managers" means the 4 managers who are not themselves.
So each manager evaluates 4 other managers.
Since there are 5 managers doing this, that's 5 × 4 = 20 manager evaluations.
Step 3: Add them together
Total evaluations = Technician evaluations + Manager evaluations
Total = 30 + 20 = 50 evaluations
Answer: C
Common traps to avoid:
A common mistake is forgetting that each manager evaluates the OTHER managers, not all 5 managers including themselves. If you counted 5 managers × 5 evaluations, you'd get 25 manager evaluations instead of 20, leading to answer D (55 or 60). Another pitfall is double-counting. Each manager-to-manager evaluation happens once (Manager A evaluates Manager B is one evaluation, not two). We're counting from the perspective of who is doing the evaluating, which is why we multiply by 5.
Key takeaway: On combination and counting problems, always identify what's being counted and from whose perspective. Break the problem into clear categories (technician evaluations vs. manager evaluations), count each category separately, then combine. Writing out "each manager does X + Y" helps you see the structure clearly and catch errors before you calculate the final answer!