Story: There are only a few gold medals left...time is running out! But wait - special headline. Mathematics has been added as an Olympic sport and the first event is finding factors. How many maths gold medals will your country's table collect - and will you beat the table behind/beside/in front of you?
Tools: Scoring template and answer guide.
Main event: Hunt for gold medals (numbers with 12 factors or more), with potentially numbers being from 0 to 120.
Gold medal = 12 factors or more
Silver medal = 10 factors or more
Bronze medal = 8 factors or more
Fourth ribbon = 6 factors or more
Prime trophy = prime number, 1 and itself only as factors
You can earn more than one gold medal and more than one of each colour of medal - aim to collect as many as you can!
Support: Draw the factors one at a time as a factor tree branching off the total. Use counters in arrays to find factors - how many rows and how many columns represents the factors.
Pro tip: Use a T-chart to brainstorm the factors. Remember, you can halve one factor and double another to find new factors. For example, a factor pair of 40 is 20 and 2. Halve one, double the other, another factor pair is 10 and 4.
Pro tip: You can also triple one factor and divide the other by 3 to find another pair. For example, a factor pair of 63 is 21 and 3. Triple one and 1/3 the other, making another factor pair of 7 and 9. The pattern works for everything - x4 factor 1/4 the other factor, and so on.
Pro tip: You can even use this strategy for large multiplications.
For example, let's say you are solving 25 x 12.
Double one factor, halve the other.
Make it 50 x 6. Do it again, double one, halve the other.
It becomes 100 x 3. It's 300.
Pro tip: Instead of a T-chart, you can also draw factor rainbows to draw the factors. Start with the number itself and 1 (21 x 1), then go smaller as you find other factor pairs (7 x 3).
Extension: Draw factor trees to find the factors. Use the prime factors to find more factors, multiplying each of the final 'branches' of the factor tree in different ways. This is the guaranteed way to ensure you have found every possible factor, since if you use a wide range of combinations of the prime factors with regular factors, you are sure to discover all the factors.
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