M3.2.8 For the adult
Choosing what to do
How do I know whether to multiply or divide?
What this chapter teaches
A bar model shows what is known and what is wanted. With equal parts, parts to total means multiply, and total to a part means divide. With unequal parts, add or take away. Problems with several steps use one operation at a time, and the answer should be checked for sense.
Three questions to ask
There is no one right wording. Listen for the idea.
- How does a bar model help you choose between multiplying and dividing?
- Why is the word "each" not a safe sign to multiply?
- How could you check that a stickers problem with four steps has the right answer?
After the chapter, the learner can
- Solve a problem with several steps using all four operations
- Draw a bar model to decide whether to multiply or divide
What they copy into their notebook
Draw a bar model. Equal parts: multiply for the total, divide for one part. Unequal parts: add, or take away a part. Do one operation at a time, and check the answer makes sense.