Question:
Mr Choo needs a total of 15 h to prepare 1800 rice dumplings. He prepares the same number of rice dumplings every hour. When his wife helps him for 4 h, 1800 rice dumplings can be prepared in 9 h.
(a) What is the average number of rice dumplings that Mr Choo’s wife prepares in the 4 hours?
(b) What is the difference in the time taken between Mr Choo and his wife if she prepares 1800 rice dumplings alone?
Solution:
![P6 / Nanyang / 2019 / SA2 / Paper 2 – Q10 [3 marks]](https://i0.wp.com/sgprimaths.com/wp-content/uploads/2020/07/P6_Nanyang_2019_Prelims_Paper2_Q10-Qns.jpg?resize=400%2C260&ssl=1)