IMC 2018 Q14
14. Which of these is equal to \(\dfrac{10}{9} + \dfrac{9}{10}\)?
- A 1
- B 2
- C \(2.0\dot{1}\)
- D \(2.\dot{1}\)
- E \(2.\dot{2}\)
Intermediate Mathematical Challenge 2018, Question 14. © UK Mathematics Trust. Original paper on ukmt.org.uk
Answer: C \(2.0\dot{1}\)
\(\dfrac{10}{9} + \dfrac{9}{10} = \dfrac{100 + 81}{90} = \dfrac{181}{90} = 2 + \dfrac{1}{90} = 2.0\dot{1}\).
Solution © UK Mathematics Trust, from the IMC 2018 solutions. Longer versions with investigations: Solutions and investigations (PDF).