Puzzles and Riddles
Learning Goals:
- Build a deeper understanding of the multiplication operation
- Solve problems involving the multiplication of one-digit whole numbers
- Communicate mathematical thinking orally and visually
The Challenge:
For each of the regions marked A to H below, think of a number that could belong in it.
Reminder: A factor of a number is a number that divides into that number with no remainder.
For example, 10 could fit in A, the “multiple of 5” region, but actually needs to go in the D region, as it is also a factor of 40 (but is not also a multiple of 4.)
Questions and Prompts to Support your Child:
- Which section did you start thinking about first? Why did you choose that section first?
- Which sections do you think have the least possibilities? Why?
- (Once a number has been found for each section) Do you think there are any other numbers that could fit as well?
Extensions & Adaptations:
- If you’re feeling stuck, try starting with the G section in the middle (find a number that is a factor of 40, as well as being a multiple of both 4 and 5)
- Once you have found one possible set of numbers, take some time to find other possibilities – 5 numbers for each section would be a good goal!
Source: The Guardian – Alex Bellos’ Monday Puzzle
Categories: Elementary