Problem 1 · 2014 Math Kangaroo
Easy
Spatial & Visual Reasoning
transformationscareful-counting
Arno lays out the word KANGAROO with 8 letter cards, but some cards are turned the wrong way (see picture). The letter K can be set right by turning its card twice, and the letter A by turning its card once. How many turns in all does Arno need so that KANGAROO reads correctly?
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Answer: C — 6
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Hint 1 of 2
Go letter by letter and decide whether each card is already the right way up.
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Hint 2 of 2
Count the cost: a letter that is upside-down or mirrored needs one or two turns to fix; add those up across the whole word.
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Approach: check each card and add up the turns it needs
- Read the laid-out word against KANGAROO and find every card that is rotated or flipped.
- Each wrong card needs either one turn or two turns to come right, exactly as the example shows for K and A.
- Adding the turns needed across all the wrong cards gives a total of 6.
- So the answer is 6.
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