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#6 Factor factory
Set by Daniel Griller
The factors of 12 are 1, 2, 3, 4, 6 and 12. It has four even factors and two odd factors, so two-thirds of its factors are even.
What fraction of the factors of 8 are even?
How many whole numbers between 1 and 100 have the property that exactly half of their factors are even?
How many whole numbers between 1 and 1 million have the property that exactly one-third of their factors are divisible by 3?
Solution next week
#5 Diagonal lines
Solution
Generally, for a shape with n vertices, there…