(Viva Voce) Chap 9 Exercise 9 Question { 8 }

Solution for Q8

Q8a) Find the average speed.

Average speed = Total Distance Travelled/Total Time Taken
                         = 360km/4 1/2h
                         = 360km/4.5h
                         = 80km/h
Ans: 80km/h

Q8b)Find the petrol consumption rate.

Petrol Consumption Rate = 360km/37.5 l
                                         = 9.6km/l
Ans: 9.6km/l

Q8c) Distance Travelled on the highway= speed X time
                                                                = 110km/h x 2h
                                                                = 220km

Remaining Distance = 360km-220km
                                 = 140km 

Remaining Time = 4 1/2h - 2h
                           = 2 1/2h

Average sped for the remaining part of journey = Total Distance Travelled/Total Time Taken 
                                                                           = 140km/2 1/2h
                                                                           = 56km/h 

Ans: 56km/h

Mavis Cheng S1-01 


  1. Hi Miss Loh,

    I will upload my video on Friday 1/7/11 .:D Thanks !Sorry for any inconvenience.


  2. Note: Comments are made reference to the clip copied submitted separately (offline).

    1. Good idea to inform the viewer what's given in the question and what the question asked to solve.

    2. Explanation for the (a) is clear :)

    3. What does the rate of petrol consumption actually mean?

    4. Explanation for (c) is very clear :)

    5. When penning down the aolution, it would be good to write on one side of the paper only.

  3. Hi Ms Loh,

    Thanks for your feedback Ms Loh. I will take note of the things I need to improve.

    Mavis :D