IMC 2012 Q13
13. Alex Erlich and Paneth Farcas shared an opening rally of 2 hours and 12 minutes during their table tennis match at the 1936 World Games. Each player hit around 45 shots per minute.
Which of the following is closest to the total number of shots played in the rally?
- A 200
- B 2000
- C 8000
- D 12 000
- E 20 000
Intermediate Mathematical Challenge 2012, Question 13. © UK Mathematics Trust. Original paper on ukmt.org.uk
Answer: D 12 000
In the rally, approximately 90 shots were hit per minute for a total of 132 minutes. As 90 × 130 = 11 700, D is the best alternative.
Solution © UK Mathematics Trust, from the IMC 2012 solutions. Longer versions with investigations: Solutions and investigations (PDF).