Which of the cones below can be formed from a 252 sector of a circle of radius

Which of the cones below can be formed from a 252

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Which of the cones below can be formed froma252sector of a circle of radius 10 by aligningthe two straight sides? (A) 10 6 (B) 10 6 (C) 10 7 (D) 10 7 (E) 10 8 2001 AMC 10, Problem #17 2001 AMC 12, Problem #8 “The slant height of the cone is 10, the radius of the sector.” Solution Difficulty: Hard NCTM Standard: Geometry Standard for Grades 9–12: Analyze properties and determine attributes of two- and three-dimensional objects. Mathworld.com Classification: Geometry > Plane Geometry > Arcs > Circular Sector Geometry > Solid Geometry > Cones
The plane is tiled by congruent squares andcongruent pentagons as indicated. The percentof the plane that is enclosed by the pentagonsis closest to 2001 AMC 10, Problem #182001 AMC 12, Problem #10“Draw a3×3pattern.” 9 = 55 5 9 % 0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 9 9 Difficulty: Medium-hard NCTM Standard: Geometry Standard for Grades 9–12: Analyze properties and determine attributes of two- and three-dimensional objects. Mathworld.com Classification: Geometry > Plane Geometry > Polygons
Patwantstobuyfourdonutsfromanamplesupply of three types of donuts:glazed, chocolate,and powdered.How many different selections arepossible? 2001 AMC 10, Problem #19“Apply Gauss’s Backward Formula (also known as barsand stars).” Mathworld.com Classification: Applied Mathematics > Numerical Methods > Finite Differences > Gauss’s Backward Formula