A Visual Numbers Match Trivia Quiz

There are 52 cards in a standard deck of French-suited playing cards. Each suit (hearts, diamonds, clubs, and spades) contains 13 ranked cards; the first card of each suit, containing a single pip, is called "ace". The last three cards, which are reversible, are called court or face cards: they are the jack (or knave), the queen, and the king. Some decks also include a number of jokers (usually two), which do not belong to any suit and are a relatively modern (late 19th century) invention.

The modern French-suited deck has its origins in the Egyptian Mamluk decks brought to Europe in the 14th century, which also contained 52 cards. The other two categories of playing cards - Latin and Germanic - use different suits, and generally have a lower number of cards.

Like octopuses, squid are mollusks of the class Cephalopoda; however, they have ten limbs instead of eight - their eight short arms being augmented by two long tentacles used to grab prey. Squid have elongated bodies, with a small internal "skeleton" made of a flat, blade-like piece of chitin. Widely used for food around the world, they are often referred to by the Italian name of "calamari" (which means "inkpots").

The photo shows a steel and copper sculpture of a giant squid that hangs in the atrium of Seattle's famous Pike Place Market. If you click on the photo, you will be able to see this creature's eight arms and two long, curly tentacles. The giant squid and the even bigger colossal squid - both of them deep-ocean dwelling creatures, very rarely (if ever) sighted by humans - are the two largest invertebrate species. Frequently preyed upon by sperm whales, those huge creatures have often been featured as sea monsters in mythology and literature.

Most modern pianos have 88 keys - 52 white and 36 black - covering seven octaves plus a minor third. There are, however, some pianos that have an extra number of keys, such as the 97-key Imperial Bösendorfer. Piano keys were traditionally made of ebony (the black ones) and ivory (the white ones): now that the ivory trade is severely restricted, or even illegal in some countries, high-quality plastics are generally used.

Though classified as a keyboard instrument, the piano is actually a cross between a stringed and a percussion instrument, as the sounds are produced by a set of wooden hammers striking the strings. Its name is a shortening of the Italian word "pianoforte" (meaning "soft-loud"). The piano's invention is credited to Bartolomeo Cristofori, an Italian harpsichord maker active from the late 17th century to the early 1730s. The photo shows a grand piano manufactured by Steinway and Sons; the other basic piano configuration is the upright (or vertical) piano.

The photo shows a haiku, the Japanese poetic form that has been popular in the West since the early 20th century. A traditional Japanese haiku consists of 17 phonetic units (which correspond to syllables), arranged in a 5-7-5 pattern, and generally printed on a single line - with a "cutting word" ("kireji") placed at the end of one of the three phrases to mark a rhythmic division (caesura). English-language haikus, on the other hand, are usually printed as three lines, with the kireji replaced by a dash or ellipsis.

The most common themes of haikus are nature and the seasons - as reflected by the haiku in the photo. Haikus are now written in many languages for all kinds of occasions, and haiku competitions are held in a variety of settings, such as schools, public transportation, and city neighbourhoods. The World Haiku Association, founded in 2000, holds regular meetings and conferences, as well as showcasing its members' poetic output on its website.

A chessboard has 64 squares, arranged in 8 rows (ranks) by 8 columns (files). The number of squares is the exact double of the total number of chess pieces - 16 white and 16 black (32). The modern chessboard derives from the Ashtapada board, which was used to play Chaturanga, the ancient Indian game that predates chess. The squares on the Ashtapada board, however, were all the same colour: the current chequered pattern dates from the 10th century AD, when chess was introduced in Europe from Asia.

Chessboards can be made of various materials, and are also found as decorative elements in parks, gardens, or city squares. Some outdoor chessboards are so large that they use humans as chess pieces. The most famous of these is located in the main square of the Italian city of Marostica, near Venice, where a famous chess game is played in even-numbered years, with people in Renaissance costume acting as chess pieces.

There are 33 letters in the modern Russian alphabet, derived - like many other alphabets used in Eastern Europe and Western and Central Asia - from the Cyrillic script, which was first developed in Bulgaria in the 9th century AD. The Russian alphabet was reformed in 1918, following the Russian Revolution, and four letters were eliminated. A previous reform, in the mid-18th century, had led to the elimination of eight letters. The Mongolian Cyrillic alphabet is directly derived from the Russian one, with two additional characters.

Of the 33 characters included in the modern Russian alphabet, 20 are consonants, 10 are vowels, one is a semivowel (similar to the English "y"), and two are modifier letters that change the pronunciation of a preceding consonant or following vowel. There are also conventions for rendering words of foreign origin that contain sounds not present in the Russian alphabet - as is the case of the English "h" or "th".

The number 5 is sacred in Islam. The fundamental practices to be followed by all adherents to the religion are known as the "Five Pillars of Islam". In Sunni Islam, they are the declaration of faith ("Shahada"), prayer ("Salah"), almsgiving ("Zakat"), fasting ("Sawm"), and pilgrimage to Mecca ("Haji"). In Shia Islam, the five foundational beliefs differ from those listed above (with the exception of the first); prayer, almsgiving, fasting, and pilgrimage are instead included in the list of additional ten practices referred to as "Ancillaries of the Faith". The Five Pillars are mentioned in the Koran, but described in detail in the text known as Hadith of Gabriel.

Muslims are also required to pray five times a day. These prayers, considered "fardh" (a religious duty commanded by God), are named Fajr (dawn), Zuhr (noon), Asr (afternoon), Maghrib (sunset), and Isha (night). The photo shows the Süleymaniye Mosque in Istanbul (Turkey), with its imposing dome and four minarets.

Valentine's Day is celebrated every year on 14 February, when the Western Christian Church honours Saint Valentine, a 3rd-century martyr who - according to a widespread legend - performed secret Christian weddings for couples in order to allow the husbands to avoid conscription into the Roman army. Saint Valentine is venerated as the patron saint of the city of Terni, in the central Italian region of Umbria, believed to have been his hometown.

The Feast of Saint Valentine commemorates what is traditionally held as the date of the saint's martyrdom on 14 February 269. Its association with love and romance, however, probably dates from the Late Middle Ages: one of the earliest references to Valentine's Day as a special day for lovers appears in Geoffrey Chaucer's "Parliament of Birds" (14th century).

79 is the atomic number of gold, whose symbol is Au (from "aurum", the Latin name of the element). Gold is a transition metal, part of group 11 in the periodic table of elements. It is found in nature in a variety of states, including native state (not combined with other elements). Prized for its lustrous, vivid yellow appearance and its quality of being resistant to most acids, gold has been used since antiquity for coinage, jewellery, and other decorative arts. Culturally, it has been associated with both the sacred and the profane, and is a symbol of wealth, power, and royalty.

Though for a long time South Africa was the world's leading gold producer, in recent times it has been overtaken by China. Other major gold-mining countries are Russia, the US, Canada, and Australia. Being highly malleable when pure (24k), gold needs to be alloyed with other metals before it can be used in jewellery. There are also naturally occurring alloys, such as electrum - an alloy of gold and silver also known as "green gold".

There are 25 cents in a US quarter dollar (known simply as "quarter"). In other countries, it is more common to find 20-cent pieces, which correspond to one-fifth of the basic currency unit. The quarter, on the other hand, was based on the Spanish silver dollar, which was also called a "piece-of-eight" due to the practice of dividing coins into eight wedges - hence the common nickname of "two bits" (two-eights) for the quarter.

Quarters have been minted since 1796; while they were originally made of silver, the current ones are made of copper and nickel. The profile of George Washington, the country's first president, appears on the obverse, while the design on the reverse has frequently changed since 1999. The photo depicts the reverse of the original version of the Washington quarter - designed by sculptor John Flanagan, and minted between 1932 and 1998.