Unknown in Multiplication & Division
Determine the unknown whole number in a multiplication or division equation relating three whole numbers (e.g. 8 × ? = 48, ? × 6 = 42)
What a learner can do afterwards
- Find the missing factor in 7 × ? = 63
- Find the missing dividend in ? ÷ 5 = 9
- Explain the strategy used (e.g. using the related multiplication fact)
1 · Read
Sometimes a multiplication or division sentence has one number missing, shown as a question mark. It might look like 8 × ? = 48, or ? ÷ 6 = 7. Your job is to figure out what number belongs there.
Look at 7 × ? = 63. You already know that division undoes multiplication, so 63 ÷ 7 tells you what number times 7 makes 63. That means ? = 9.
Now look at ? ÷ 5 = 9. Some number split into 5 equal groups makes 9 in each group. Multiply back: 5 × 9 = 45. So ? = 45.
Always check your answer by putting it back into the original sentence. If both sides match, you found the right number.
Find a missing number by using the multiplication fact you already know, then check it by multiplying back.
2 · Watch
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