A committee of k members was formed from the n members of a certain company's board of directors. Each member...
GMAT Two Part Analysis : (TPA) Questions
A committee of \(\mathrm{k}\) members was formed from the \(\mathrm{n}\) members of a certain company's board of directors. Each member of the committee sent exactly one email summarizing his or her perspective on the committee's findings to each board member who was not a member of the committee, and to no one else. The total number of these email summaries sent was \(\mathrm{35}\).
Select values for k and for n that are jointly consistent with the given information. Make only two selections, one in each column.
Phase 1: Owning the Dataset
Visualization
Let's create a simple diagram to understand the email flow:
Board of Directors (n members total) ┌─────────────────────────────────────┐ │ Committee (k) │ Non-Committee │ │ │ (n - k) │ │ ● ● ● ... ● │ ○ ○ ○ ... ○ │ │ k members │ (n-k) members │ └─────────────────────────────────────┘ ↓ Each ● sends one email to each ○ Total emails = k × (n - k) = 35
Understanding the Problem
- We have n board members total
- k members form a committee
- Each committee member sends exactly one email to each NON-committee member
- No emails sent within the committee or to anyone else
- Total emails sent = 35
Phase 2: Understanding the Question
Mathematical Relationship
Each committee member sends emails to (n - k) non-committee members.
With k committee members, total emails = \(\mathrm{k} \times (\mathrm{n} - \mathrm{k}) = 35\)
What We're Looking For
We need values of k and n from the given choices that satisfy:
- \(\mathrm{k} \times (\mathrm{n} - \mathrm{k}) = 35\)
- \(\mathrm{k} < \mathrm{n}\) (committee must be smaller than the whole board)
- Both k and n must be from our choices: [4, 5, 6, 10, 12]
Phase 3: Finding the Answer
Systematic Testing
Let's test each possible value of k:
If k = 4:
\(4(\mathrm{n} - 4) = 35\)
\(4\mathrm{n} - 16 = 35\)
\(4\mathrm{n} = 51\)
\(\mathrm{n} = 12.75\) (not an integer, so invalid)
If k = 5:
\(5(\mathrm{n} - 5) = 35\)
\(5\mathrm{n} - 25 = 35\)
\(5\mathrm{n} = 60\)
\(\mathrm{n} = 12\) ✓
Verification: \(5 \times (12 - 5) = 5 \times 7 = 35\) ✓
? Stop here - we found our answer.
Phase 4: Solution
Final Answer
- Statement 1 (k): 5
- Statement 2 (n): 12
The committee has 5 members from a board of 12 members. Each of the 5 committee members sends one email to each of the 7 non-committee members, totaling \(5 \times 7 = 35\) emails.