After the completion of grade 7 maths, we carry on to grade 8 work.  Learners will see that the work doesn't differ that much, only that the work gets more, and more difficult.  

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Starting off with problem solving, in grade 7, learners learnt about steps involved in problem solving.   

Revision of what was done in grade 7:

1. Understand the problem (What do you know? What do you need to find out?)
2. Develop a plan:  Have you solved a similar problem?  
3. Solve the problem (Do you need to try any other strategies? What is the solution?)
4. Look back (Did you answer the question correctly?  Is the answer you gave, reasonable?)

Example:

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The Peters family is driving from one city to another .  The distance between the 2 cities is 600km.  The Peters family have been driving for 3 hours at 100km/h.  If they increase the speed to 120km/h, how much longer will it take them to reach their destination?

Using the steps to do the example above:

1.  Understand the problem:

We know that the Peters' family has completed a part of their journey already.  We need to find out how long the rest of their trip will take.

Understand the problem

2.  Develop a plan:

Recall the formulae for distance(d), speed(s) and time(t), as the example is about speed, distance and time.

After 3 hours the Peters' family already drove 3 x 100km= 300km.

The total distance of their trip is 600km.  We can subtract the distance they drove with the total distance.  

Therefore:  600 - 300 = 300km which they still have to drive.

We also know that after 300km they increased their speed to 120km/h so this mean that they will drive the rest of their trip a bit faster.

Think of a plan

3.  Solve the problem

Draw a picture of the situation to help you solve the problem

After 3 hours, at a speed of 100km/h they drove 300km.  They still have another 300 km to go, but for this 300km they are driving at a speed of 120km/h.  The time taken for this part of the journey is 300 km ÷ 120km/h which is equal to 2hours and 30 minutes.  The distance they still have to travel is 300 km and it will take them 2 and a half hours to reach their destination.

Solve the problem

4.  Look back

Does the answer make sense to you?  Yes, if they travelled at a speed of 100km/h and it took them 3 hours, obviously driving at a faster speed must get them at their destination faster.  The distance that they have travelled and still have to travel is the same.

Problem solving is a part of our lives, everyday.