Problem 2 · 2012 Math Kangaroo
Easy
Counting & Probability
careful-counting
Barbara wrote “KAENGURUWETTBEWERB” on the blackboard. She used the same colour for equal letters and a different colour for different letters. How many different colours did she use?
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Answer: D — 10
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Hint 1 of 2
Same letter means same colour, so count how many different letters appear.
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Hint 2 of 2
List the distinct letters in KAENGURUWETTBEWERB and count them.
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Approach: count distinct letters
- Each distinct letter needs its own colour; repeated letters reuse a colour.
- The distinct letters are K, A, E, N, G, U, R, W, T, B.
- That is 10 different letters, so 10 colours.
Mark:
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