P6 / Raffles Girls / 2020 / SA2 Prelims / Paper 2 – Q08 [4 marks]

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: