Stage: 3 Challenge Level: 
Consider all of the five-digit numbers which we can form using only
the digits 2, 4, 6 and 8.
If these numbers are arranged in ascending order, what is the 512th number?
If these numbers are arranged in ascending order, what is the 512th number?
Properties of numbers. Mathematical reasoning & proof. Number bases. Combinations. Comparing and Ordering numbers. Place value. Divisibility. Integers. Factors and multiples. Permutations.
Published October 1997.
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