IMC 2007 Q1
1. At midnight on 15 December 2005, the moon reached its highest point in the sky, an event which occurs every 18.6 years. In which year will it next occur?
- A 2007
- B 2008
- C 2023
- D 2024
- E 2191
Intermediate Mathematical Challenge 2007, Question 1. © UK Mathematics Trust. Original paper on ukmt.org.uk
Answer: D 2024
The date 18 years after 15 December 2005 will be 15 December 2023. Since a further 0.6 years, i.e. just over 7 months, will then elapse, the moon will next reach its highest point in the sky in 2024.
Solution © UK Mathematics Trust, from the IMC 2007 solutions.