ITPEC FE Morning October 2023 Question 51

Communication channels (combinations) — calculate additional one-on-one meetings when team grows.

Formula: C(n, 2) = n × (n - 1) / 2

• •With 10 members: 10 × 9 / 2 = 45 meetings
• •With 12 members: 12 × 11 / 2 = 66 meetings
• •Additional meetings: 66 - 45 = 21

Why not others:
- (a) 12 — counts only new-to-old meetings (2 × 10 = 20), still wrong
- (c) 22 — double-counts the meeting between the two new members
- (d) 42 — uses permutations (n × (n-1)) instead of combinations

Key rule: Each unique pair meets once → use n(n-1)/2. This is the same formula used for communication channels in project management.

AI-generated — may contain errors