Library / UKMT Grey Kangaroo /172 of 242

UKMT Grey Kangaroo, 2021

Combinatorics Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

In a tournament each of the six teams plays one match against every other team. In each round of matches, three take place simultaneously. A TV station has already decided which match it will broadcast for each round, as shown in the diagram. In which round will team S play against team U?

(A) $1$ (B) $2$ (C) $3$ (D) $4$ (E) $5$

Figure for this problem

We don't reproduce this publisher's solutions. Their own solution is here — work the problem first.

Want a route through all this instead of an archive? The track puts 2,604 problems in a working order, from Junior Challenge level to the IMO shortlist.

Source: UK Mathematics Trust, licensed © UK Mathematics Trust; past papers published free at ukmt.org.uk. Statement reproduced verbatim; metadata (topic, difficulty) added by this project. Solutions are the publisher's, linked not copied.