Questions tagged [geometry]
A puzzle related to shapes, geometric objects (polygons, circles, solids, etc.) of any number of dimensions, the relative position of figures, and the properties of space. Use with [mathematics]
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Can a 10*10 square be paved with 1*4 rectangular stone plates?
Can a 10 * 10 square be paved with 1*4 rectangular stone plates?
I seek a very intuitive and simple answer to this puzzle.
P.S. Will post the source later. The source contains the answer but it is not ...
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Find side view and simple 3d [closed]
You need to find a side view of B) nacrt=front view tlocrt=top view. You also need to draw the 3d model. I got this puzzle from my teacher in school.
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Crossing a square pond with beams
Here is a classical mathematical puzzle:
In the middle of a square pond lies a square island (whose sides are aligned with the sides of the pond). On the island is a tower with a princess locked ...
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Regular pentagram inscribed in a parabola
The diagram shows a regular pentagram inscribed in a parabola.
Can another red pentagon (congruent to the one shown) fit in the gray region?
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Three-cushion billiards challenge.
World champion three-cushion billiards player can perfectly make a billiard ball end where asked for (if possible), on a standard rectangular shaped competition table.
The champion now, for ...
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A "crappy" pentagon puzzle
Lately, we've had plenty of puzzles based on the regular pentagon and its geometric properties. So I propose one that literally brings it all together.
Use eleven copies of the larger (left) piece ...
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Sliding coins down an envelope
The envelope is a regular pentagon with two diagonals. The red coins are two vertically aligned and touching congruent circles, the top one passing through the apex of the pentagon, and the bottom ...
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Two semicircles in a parallelogram
Two congruent semicircles (blue) are inscribed in the two triangles formed by the short diagonal (black) of a parallelogram (also black) as shown below. The short diagonal has the same length as the ...
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Heptagons trompe-l'œil ?
Seven outer blue, equal sized, regular heptagons touch the sides of a given, also equal sized, inner blue regular heptagon.
The green triangle has black vertices: the south and the, up to one, most ...
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A single magical ant wandering in a vast garden of cubes
The following image depicts a small part of a vast "cube garden":
This garden started as a single 1x1x1 cube, which was grown into the complex shape you see here by performing the following ...
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Can another circle fit in this diagram?
Two vertically-aligned and touching congruent (blue) circles are inscribed in a pendant (the black quadrilateral) in a regular star as shown below. Can you fit another circle of the same size that’s ...
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Circles in a pendant in a star
Four vertically-aligned touching circles of equal radius are inscribed in a pendant (the black quadrilateral) inside a regular star as shown in the figure below. Show that the centre of the green ...
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Two semicircles in a regular pentagon
Two semicircles, pink and blue, are inscribed inside a regular pentagon as shown in the figure. Which semicircle is bigger?
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Two triangles in a light bulb
Here’s a light bulb made of a regular dodecagon (yellow), two equilateral triangles (light gray), and a square (dark gray). Show that the red and blue triangles have the same area.
Of course, you can ...
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Show that the area of the region inside this square and regular pentagon is greater than 3/4
A square and a regular pentagon, each of area 1, are coplanar and concentric. Show that the area of the region inside both shapes is greater than 3/4.
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