Numerical General Knowledge Trivia Quiz

The 1975 film 'Three Days of the Condor' was a political thriller staring Robert Redford as a CIA researcher whose workmates are all killed while he is out getting lunch. Faye Dunaway plays the woman who assists him in working out who is responsible for the massacre, while he tries to avoid sharing their fate. Intricate layers of spy networks and hired assassins emerge, before our hero appears to have emerged unscathed. Maybe.

I recently rewatched this film as part of a weekend-long binge following the news of Robert Redford's death on 16 September 2025 at the age of 89. Although his ability to hold a camera and make the audience believe in him was apparent, this is really a lesser film than some of the others from that time. If you want to see Robert Redford in a political thriller, I would heartily recommend 'All the President's Men' (with Dustin Hoffman), released in 1976. From a bit earlier in has career come 'Butch Cassidy and the Sundance Kid' (1969, with Paul Newman) and 'The Way We Were' (1973, with Barbra Streisand). Maybe it's just because I was younger then, but those films were magical at the time, and still seem to me to bear repeated viewing.

The Chinese flag has a red field with five gold stars. One large star is in the upper left corner, with the other four arranged in an arc within the top left quadrant. The red color (a shade called Chinese red) represents the Communist revolution that had just taken place when this flag was adopted in 1949. The large star represents the Chinese Communist Party. The four smaller stars were said by the flag's designer, Zeng Liansong, to represent the four classes of Chinese society as defined in a speech by Mao Zedong titled 'On the People's Democratic Dictatorship': scholars, peasants, workers, merchants. Their arrangement in an arc around the large star demonstrates the way the Communist Party brings the entire society together.

This was only one of the designs submitted for selection as the national flag. The one preferred by Mao Zedong had one large star and a horizontal gold strip to represent the Yellow River. The guidelines for proposed flags specified the shape and the red field, and indicated that the symbols must reflect Chinese culture (including geography and history) and show the power of the people's democratic government based on the worker-peasant alliance. The final winner was considered controversial because of its inclusion of scholars and (even more) merchants. Zeng's original design had a red hammer and sickle inside the largest star, but that was removed to avoid looking like an imitation of the flag of the USSR.

'The House of the Seven Gables' was published in 1851, with the subtitle 'A Romance'. It is a work in the Gothic genre, meaning the atmosphere is primarily of fear and/or guilt. It was inspired by an actual house in Salem, Massachusetts which belonged to his cousin (and previously to some of his ancestors who had been involved in the 17th century Salem Witch Trials).

The house at the centre of the story has been haunted since its first construction on land that had been taken from a man wrongfully condemned for witchcraft, who laid a curse on the family of those responsible at his execution. Over a century later, the current members of the Pyncheon family face a range of (possibly supernatural) misfortunes, before their ultimate triumph over adversity - following which they leave their past behind, moving to a new house in the country.

The exact number and names of the muses who inspired human creativity in various fields of endeavour varied over time, but by the Classical period (during the 4th and 5th centuries BCE) they were consolidated as nine. In alphabetical order, they were named Calliope, Clio, Erato, Euterpe, Melpomene, Polyhymnia, Terpsichore, Thalia, and Urania. By the Hellenistic period (a period of roughly 300 years between the death of Alexander the Great in 323 BCE and the death of Cleopatra VII in 30 BCE) their functions had settled into an association of each with a specific area. Someone undertaking to create a new work would often start by invoking the relevant muse, asking their assistance and hoping the work would be a satisfactory offering.

The most commonly-found lists of the association of each muse is: Calliope, epic poetry and general eloquence; Clio, history; Erato, lyric poetry, especially erotic poems; Euterpe, music, and later lyric poetry; Melpomene, theatrical tragedy; Polyhymnia, sacred poetry, hymns and mime; Terpsichore, dance, both solo and chorus; Thalia, comedy and pastoral poetry; and Urania, astronomy. Of course, as is the case for most Greek mythological figures, there are variants recorded at different times and in different places. And even this list shows clear areas of overlap - not surprising, given that words, music and movement are all involved in most of these areas!

South America has twelve sovereign countries: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela. In addition, the region of French Guiana (located in the north, between Suriname and Brazil, is an overseas department of France. Offshore, but still considered geographically part of South America, there are two more dependencies: the Falkland Islands, and South Georgia and the South Sandwich Islands, both under British control despite Argentinian claims.

That is the official situation, but those who like to find points to debate may offer some further suggestions for possible inclusion in South America. For example, some argue that Panama, the Central American country that contacts the northwest corner of South America, could be included, because it was part of Gran Colombia during Spanish colonisation. Since the Caribbean nation of Trinidad and Tobago is actually on the South American continental shelf, it could be argued to belong there rather than grouped with the Caribbean islands. The same can be argued for the Netherlands-controlled islands of Aruba, Bonaire and Curaçao, but they aren't independent nations.

The flag of the United States of America has a blue canton with white stars whose number is equal to the number of states - at the time of writing this quiz, that is 50. The main field of the flag consists of red and white stripes - 7 red, 6 white - representing the 13 original colonies that established the nation following independence from British rule in the American Revolution.

This is the 27th official US flag since the first one was adopted in 1777. The first change was made in 1795, when the addition of Vermont and Kentucky to the Union led to a flag with 15 stars and 15 stripes. Then the next few states were not recognised, partly due to the messiness that was being created in the flag. In 1818 a new Flag Act was passed that decreed there would be 13 stripes, with new states recognised only by a star. This flag had 20 stars. It was not until the 48-star flag was adopted in 1912 that the arrangement of the stars was specified - before that, every flag maker could indulge their own creative urge.

Douglas Adams's science fiction series that started with 'The Hitchhikers' Guide to the Galaxy' sets up a world in which a "pan-dimensional, hyper-intelligent species of beings", searching for the Answer to The Ultimate Question of Life, the Universe, and Everything, is disappointed when their super-computer takes seven and a half million years to announce that the answer is 42, and informs them, "that quite definitely is the answer. I think the problem, to be quite honest with you, is that you've never actually known what the question was." Undeterred, they plan to set up a bigger computer to try again - Earth, the planet that is destroyed by the Vogons at the start of the first book to construct an intergalactic hyperspace bypass, moments after the ten-million-year-long calculation was complete, but before it was communicated.

Of course, we don't learn this in a linear fashion - the story unfolds over multiple books, each with their own ostensible plot, each forming part of the patchwork that is, apparently, our universe. At the end of 'The Restaurant at the End of the Universe', Arthur Dent (convinced that the answer is embedded somewhere inside his head), engages in a game of Scrabble. After his caveman opponent (don't ask) spells fortytwo, he pulls out tiles to try and construct the question. His letters spell out "What do you get if you multiply six by nine?". The final sentence (in some editions of the book) reads: "I always thought something was fundamentally wrong with the universe."

Why 42? Books have been written discussing possible significant reasoning, implications, and so forth. Adams was adamant that he just chose a smallish, innocuous number.

Mercury, the planet closest to the sun in our galaxy, obviously has a smaller orbit to cover as it circles the sun, so you would expect it to take less time. Because it also moves faster due to its proximity to the sun, it only takes 88 Earth days to complete an orbit.

It takes Mercury 58.65 Earth days to rotate once on its axis relative to the stars (called a sidereal day). Combining this slow spin with its rapid orbit, the length of a solar day (between consecutive sunrises) is about 176 days, or two years. For one Mercurian year the same half of the planet is in sunlight, while it is then in darkness for the next Mercurian year of 88 days. Now that would really play havoc with your circadian rhythms!

We could have used a Gregorian calendar, as it would slot into this spot (365-366 days in a year) instead of the Islamic calendar (354-355 days), but wouldn't you rather learn why the Islamic calendar is that length? The Lunar Hijiri calendar, as it is also called, is based on lunar cycles, and a year has 12 lunar months. Since a lunar month is about 29-30 days (this is not the time to discuss the various definitions of a lunar month, and how they differ), 12 months gives 354-355 days in a year. This is why the date of Islamic celebrations seem to move around the year for those who use a Gregorian calendar - each year starts about ten days earlier than the last one.

The Hijiri calendar uses for its starting year 622 CE, the date of the Hijrah, when Muhammad and his followers moved from Mecca to Medina and established the first Islamic community. Each lunar month starts when the new crescent moon for the month first appears - since this varies around the world on any given date, it is usually decreed as the day when this happens in Mecca. Some Islamic groups prefer to have the months alternate in length neatly, 29 days alternating with 30 days.

While some of the earlier numbers may have been a bit close to each other, this one is way larger than any of them: light travels approximately 300,000,000 metres in a second. The number is given here to one significant figure, because the exact value varies as the light is travelling through different media - which is what creates a spectrum when it shines through a prism of the right shape, and makes a spoon sitting in a clear glass of water look to be broken in two separate pieces when you look at it from the side.

I could more precisely say that light travels 299,792,458 m/s in a vacuum. This is the number represented by the letter c in Einstein's Theory of Special Relativity, and which appears in the famous mass-energy equivalence statement E=mc^2. When you multiply c by itself, you get something close to 90,000,000,000,000,000 - so a tiny amount of mass lost during a nuclear reaction produces a truckload of energy!