CAT 2007QA Question 11

Permutation & CombinationEasy
Passage / Data

Answer the next 2 questions based on the information given below.

Cities A and B are in different time zones. A is located 3000 km east of B. The table below describes the schedule of an airline operating non-stop flights between A and B. All the times indicated are local and on the same day.

Assume that planes cruise at the same speed in both directions. However, the effective speed is influenced by a steady wind blowing from east to west at 50 km per hour.

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In a tournament, there are n teams T1 , T2 ....., Tn with n > 5. Each team consists of k players, k > 3. The following pairs of teams have one player in common:

T1 & T2 , T2 & T3 ,......,  Tn − 1 & Tn , and Tn & T1.

No other pair of teams has any player in common. How many players are participating in the tournament, considering all the n teams together?

Answer & solution

  • n(k – 1)

  • B

    k(n – 1)

  • C

    n(k – 2)

  • D

    k(k – 2)

  • E

    (n – 1)(k – 1)

Solution

Each team has (k – 2) players to itself and shares 2 players with other two teams.

n pairs of teams have 1 player in common and there are n teams.

Total number of players = n(k – 2) + n
= nk – 2n + n
= nk – n
= n(k – 1)

Hence, option (a).

CAT 2007 QA Q11: In a tournament, there are n teams T 1 , T 2 ....., T n with n > 5. Each team consists of k players, k > 3. Th — Solution | TheCATExam