Questions that deal with Speed tend to get very routine and predictable. As of writing, there are only a couple of heuristics on are constantly used on it – “Common Distance” & “Common Time”. One thing I emphasise to my students is the need to expand their knowledge and push themselves further than the norm. The heuristic used in this question is the first time I have realised for public viewing. It will only be available on Chris Academy’s learning portal. Unfortunately, it will not be ready in time for PSLE 2018 students unless they are having private lessons taught by me.
I have success teaching my Pri 5 students this method even before they have learnt the topic of speed. After learning the method, they are easily able to visualise the problems much quicker and solve without any prompting.
These are the steps to solving the question. This heuristic will be taught in the Online Portal
82 ✖️ 2 = 164
194 ➖ 164 = 30
82 ➖ 76 = 6
30 ➗ 6 = 5
Answer: 5 hours