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### Math Puzzles & Brain Teasers

The Creeper on the Tree

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 Hide all answers   View all answers   Print   Try the Quiz 1. A creeper plant is climbing up and around a cylindrical tree trunk in a helical manner. The tree trunk has a height of 360 inches and a circumference of 48 inches.If the creeper covers a vertical distance of 90 inches in one complete twist around the tree trunk, what is the total length of the creeper? Answer: 408 Solution: To make visualization easy, it is convenient to conceptually open out the bark of the tree trunk and flatten it. The cylindrical surface will then be a rectangle (as illustrated in the figure alongside for 4 twists of the creeper). It may be noted that: Width of the rectangle = Circumference of the cylinder = 48 inches. Height of the rectangle = Vertical distance on the cylinder = 90 inches (in one twist). Using the Pythagorean Theorem for a right-angled triangle, Length of the hypotenuse = (482 + 902) 1/2 = 102 inches. Now, the number of twists the creeper makes around the tree trunk is 4 (= 360 / 90). If the length of the creeper (as given by the hypotenuse) is 102 inches in one twist, then the total length of the creeper in 4 twists is 408 inches. Food for thought: Is the total length of the creeper in the above calculation the actual length or the minimum length?   Try the Quiz :     Puzzles & Brain Teasers : The Creeper on the Tree