Dividing? Think about Multiplying First

Achievement Objectives
NA3-2: Know basic multiplication and division facts.
Specific Learning Outcomes

Recall multiplication to 10 x 10, and the corresponding division facts.

Recall groupings of twos, threes, fives, and tens that are in numbers to 100 and the resulting remainders.

Description of Mathematics

Number Framework Stage 6

Required Resource Materials
Counters or similar objects
Activity

Set a problem involving a multiplication fact that the students know by instant recall: “Five children have 15 sweets altogether. How many does each have?” Let the students model 15 objects in pairs or small groups. Ask how many groups have to be created (5). Without touching the 15 objects, ask the students to imagine how many each child gets and to discuss why they think this is so. Check by sharing out the objects. Record 15 ÷ 5 = 3 on the board or modelling book. Link this problem to the multiplication fact 5 x 3 = 15 (not 3 x 5 = 15).

Repeat for other multiplication facts that the students know by instant recall.

Activity – Advanced Additive Onwards

Set a problem like: “Seventeen lollies are shared among three children. How many will each child get?” Suppose an answer like two comes up, record 5 x 2 = 10 on the board or modelling book and ask, “How many will be left over?” “Is there enough for everyone to have another lolly?” (Yes.) “How many does everyone now have?” (Three.) “Now is there enough for everyone to have another lolly?” (No.) “Why not?”

Now record 17 ÷ 5 = 3 with 2 left over on the board or modelling book.

Repeat with similar examples.

 
 

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