Beyond the answers - interesting background to this quiz

Why 23 is a prime number worth remembering

Prime numbers are integers greater than 1 that have exactly two divisors: 1 and themselves. The number 23 fits that rule perfectly, which is why it appears so often in puzzles and number theory. By contrast, 33 and 63 are both divisible by 3, making them composite. Small primes like 23 are building blocks for much of modern mathematics, including the encryption systems that protect online communication.

The Seven Years’ War - a conflict before the world wars

The Seven Years’ War began in 1756 and involved most of the great European powers of the time. It also spread far beyond Europe, with fighting in North America, the Caribbean, West Africa, and India. Some historians describe it as a genuinely global conflict, predating the world wars by more than 150 years. The war reshaped colonial holdings, particularly between Britain and France, and set the stage for later imperial rivalries.

How Greenwich became the starting point of longitude

The prime meridian, or 0 degrees longitude, runs through the Royal Observatory in Greenwich, London. This was agreed internationally at the International Meridian Conference in 1884, largely because British nautical charts were already widely used. Before that, different countries often used their own reference lines, which caused confusion in navigation and mapmaking. Today, Greenwich remains the reference point for world time zones and global positioning.

Edinburgh - the Athens of the North

Edinburgh earned the nickname "Athens of the North" during the 18th and 19th centuries, a period when the city became a major centre of philosophy, science, and literature. Figures such as David Hume and Adam Smith were connected to the Scottish Enlightenment, and the city’s neoclassical architecture deliberately echoed ancient Greek styles. The comparison to Athens was both intellectual and visual, celebrating learning and classical design.

Les Misérables and its long journey through the 19th century

Victor Hugo wrote Les Misérables over a period of roughly two decades, and it was published in 1862, squarely in the 19th century. The novel explores poverty, justice, and redemption in post-Napoleonic France, following characters such as Jean Valjean. Hugo wrote parts of it while in exile, and the book became an immediate commercial success despite mixed critical reception at the time.