Fried Rice

Task 63 ... Years 2 - 8

Summary

For some students, the materials in this problem are really an aid to logical thinking rather than a measuring exercise. The challenge is to make particular masses using containers that limit what can be measured. The story shell provides a possible reason why someone might have to do this. 		 

Materials

  • 1 x 50g and 1 x 30g container
  • rice and a spoon

Content

  • measuring mass
  • addition and subtraction
  • problem solving
Fried Rice

Iceberg

A task is the tip of a learning iceberg. There is always more to a task than is recorded on the card. 		   

Question 1
Students need to realise that the difference between the 50g and 30g containers is 20g. So filling the 50g and pouring it into the 30g would leave 20g in the 50g container. Storing this and repeating the exercise would produce a total of 40 grams.

Question 2
The clue is that filling the 30g twice and pouring it into the 50g would leave 10g in the 30g container at the moment when the 50g container was full.

  • Solving the problem shows these two cups are all that is needed to measure 10g, 20g, 30g, 40g and 50g. Are there any other masses which could be accurately measured with these cups?
  • Find all the masses that can be measured with 1 x 20g and 1 x 50g cups.
  • Choose two cup sizes of your own. Find all the masses that can be accurately measured with your cups.
  • Explore whether similar problems can be created using containers for measuring millilitres.

Whole Class Investigation

Tasks are an invitation for two students to work like a mathematician. Tasks can also be modified to become whole class investigations which model how a mathematician works. 		   

Rather than use this as a whole class investigation with everyone simultaneously, it is better (from the point of view of rice on the floor) to set up the task at a work station and rotate the students through it over a couple of days. Follow this with a class discussion which summarises what has been discovered and raises the 'What happens if...? questions. Students can then follow these up in groups according to the cups chosen, or assigned.

At this stage, Fried Rice does not have a matching lesson on Maths300.

Is it in Maths With Attitude?

Maths With Attitude is a set of hands-on learning kits available from Years 3-10 which structure the use of tasks and whole class investigations into a week by week planner. 		   

The Fried Rice task is an integral part of:

  • MWA Chance & Measurement Years 3 & 4

Green Line
Follow this link to Task Centre Home page.