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Printimc
geometry intermediate
Problem
A white cylindrical silo has a diameter of 30 feet and a height of 80 feet. A red stripe with a horizontal width of 3 feet is painted on the silo, as shown, making two complete revolutions around it. What is the area of the stripe in square feet? 
(A)
(B)
(C)
(D)
Solution
The cylinder can be "unwrapped" into a rectangle, and we see that the stripe is a parallelogram with base and height . Thus, we get
Final answer
C