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2. Decomposition (1)


problem or task

Simple tasks often have simple solutions. For example, if the task is to open a door then the solution is to simply walk up to the door and open it.

But some problems are a bit more complicated - for example, a weekly trip to buy groceries. You can break down large problems like this into several smaller, simpler tasks. This is "decomposition".


The weekly shop task breaks down into five smaller tasks. These are:-

  • Budget - work out how much money you are going to spend
  • Itemise - make a list of items and make sure that you can buy them with your budget
  • Identify shop - decide which shops you are going to visit.
  • Travel - work out how to get to the shops
  • Shopping - in your chosen shops, collect the items, bag them up and pay for them. Then return home, unpack them, and put them in their correct place.

This approach can be used on any task. The skill is to be able to break up a problem into more manageable tasks and this takes practice.


Challenge see if you can find out one extra fact on this topic that we haven't already told you

Click on this link: what is problem decomposition