10 most difficult geometry riddles A list of ten (out of 20) geometry related questions that are the most often answered incorrectly Geometry quiz How is the infinity symbol called?Lemniscate refers not only to the infinity symbol but also to any geometric shape that is curved like a figure-eight.very hard 17% lemniscatelemniscate17%omniscateomniscate61%perniscateperniscate11%ettoniscateettoniscate8%Created by: Ninjai. Statistics based on 475 answers in 3 languages »names riddles » The illustration shows the figure known in mathematics as;Lune of Hippocrates,. In geometry, the lune of Hippocrates, named after Hippocrates of Chios, is a lune bounded by arcs of two circles, the smaller of which has as its diameter a chord spanning a right angle on the larger circle. Equivalently, it is a non-convex plane region bounded by one 180-degree circular arc and one 90-degree circular arc. It is the first curved figure to have its exact area calculated mathematically.very hard 24% Tales' sailsTales' sails25%Pythagorean sicklesPythagorean sickles23%Archimedes' archesArchimedes' arches25%lune of Hippocrates,lune of Hippocrates,24%Created by: Tschuka . Statistics based on 243 answers in 2 languages »mathematics riddles » During a full 24-hour day, how many times would the hands of a clock overlap?22. The minute hand makes 24 revolutions, while the hour hand makes 2 revolutions.very hard 33% 666%121221%222233%242438%Created by: globalquiz.org. Statistics based on 10938 answers in 2 languages »time riddles » In which year did Leonhard Euler introduced the symbol "i" to represent the square root of -1 ?In 1777. The letter "i" as a designation of the element from -1 was proposed by Leonhard Euler in 1777. Later, from 1801, this designation was popularized by Carl Friedrich Gauss. Currently, it is the most commonly used symbol of the imaginary unit.hard 41% in 1555in 15558%in 1666in 166625%in 1777in 177741%in 1888in 188825%Created by: Tschuka . Statistics based on 2174 answers in 2 languages »numbers riddles » What is the maximum distance a plane can fly travelling constantly North?20,004 km. Continous travel North must eventually end at the North Pole. So, the maximum distance is half of the Earth's meridional circumference, which can be reached if a plane starts at the South Pole.hard 42% 10,002 km10,002 km9%20,004 km20,004 km42%40,007 km40,007 km17%It can fly endlessly (as long it can)It can fly endlessly (as long it can)31%Created by: globalquiz.org. Statistics based on 16212 answers in 2 languages »aviation riddles » Which quadric surface is shaped like a saddle?Hyperbolic paraboloid. The widely sold fried snack food Pringles potato chips resemble a truncated hyperbolic paraboloid. The distinctive shape of these chips allows them to be stacked in sturdy tubular containers, fulfilling a design goal that they break less easily than other types of chip.hard 43% parabolic cylinderparabolic cylinder8%elliptic paraboloidelliptic paraboloid27%hyperbolic paraboloidhyperbolic paraboloid43%elliptic hyperboloidelliptic hyperboloid19%Created by: Ninjai. Statistics based on 1375 answers in 3 languages »mathematics riddles » If Earth's radius was larger by 1 meter, how much longer would its equator be?By approx 6 meters. For each circle, the length of the circumference is c=2πr. Hence, if a radius grows by 1 meter, the circumference grows by 2 π meters - no matter what the initial value of radius was.hard 45% by approx 6 metersby approx 6 meters45%by approx 6 kilometersby approx 6 kilometers17%by approx 60 kilometersby approx 60 kilometers20%by approx 6000 kilometersby approx 6000 kilometers15%Created by: SpikeMe. Statistics based on 29994 answers in 2 languages »math riddles » What is the approximate value of the golden ratio ("phi")?1.61. In mathematics, two quantities are in the golden ratio if their ratio is the same as the ratio of their sum to the larger of the two quantities. It is often used for aesthetics in art and design.hard 47% 3.143.1418%2.162.1625%1.611.6147%0.870.878%Created by: Ninjai. Statistics based on 6092 answers in 2 languages »architecture riddles » The geometrical structure depicted in the picture is called ...Spiral of Theodorus. In geometry, the spiral of Theodorus is a spiral composed of contiguous right triangles. It was first constructed by Theodorus of Cyrene.The principle of construction is based on the Pythagorean theorem.hard 49% Hippocrates hairpinHippocrates hairpin8%Spiral of ArchimedesSpiral of Archimedes27%Euclid's crustEuclid's crust14%Spiral of TheodorusSpiral of Theodorus49%Created by: Tschuka . Statistics based on 602 answers in 2 languages »mathematics riddles » A triangle can NOT have sides of ...1cm, 2cm, 3cm. The triangle inequality states that the sum of the lengths of any two sides of a triangle must be greater than or equal to the length of the third sidehard 55% 1cm, 2cm, 3cm1cm, 2cm, 3cm55%4cm, 5cm, 6cm4cm, 5cm, 6cm6%7cm, 8cm, 9cm7cm, 8cm, 9cm6%All of the answers are correctAll of the answers are correct30%Created by: lukasz Poland. Statistics based on 2163 answers in 2 languages »author: lukasz Poland riddles » Play geometry quiz and see all the questions.