Mental arithmetic, geometry, logic and vocabulary. 10 questions to wake up your inner mathematician, no calculator needed.
10 maths questions: mental arithmetic, geometry, percentages and basic vocabulary. A quick way to check that your school lessons aren't as far away as you think.
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From the pyramids of Egypt to the algorithms that run the internet, mathematics is the invisible foundation of our civilisation. It lets us count, measure, build, predict and make sense of the world around us. The basics we learn at school, the four operations, geometry and percentages, are actually used every single day: managing money, following a recipe, reading a chart or working out a discount in a shop.
This quiz needs no calculator and no complicated formulas. It focuses on the essential ideas you meet in everyday life, plus a little mathematical vocabulary. The aim is not to trick you, but to remind you that maths can be simple, useful and even fun.
All ten easy level questions, with the answer and the reasoning behind it.
Correct answer: 55
55, adding the tens first.
Correct answer: 27
27, and 2 + 7 adds up to 9, as with all the nine times table.
Correct answer: 45
45, and two lots of 45 make 90.
Correct answer: 5
Five, like the famous building in Washington.
Correct answer: 32
32, and 32 + 18 brings you back to 50.
Correct answer: 12
Twelve, or thirteen for a baker.
Correct answer: The diameter
The diameter, which is twice the radius.
Correct answer: 25
25, or a quarter of a hundred.
Correct answer: 90
90, like the corner of a page.
Correct answer: 14
14, which divides neatly by 2.
Want to warm up before playing or double-check something? Open any question to reveal the correct answer and a short explanation.
Correct answer: 56
7 × 8 = 56. It is one of the most commonly forgotten times tables, with many people hesitating between 54 and 56. A famous memory trick: the sequence '5, 6, 7, 8' reads as 56 = 7 × 8.
Correct answer: 6
A hexagon has 6 sides. The Greek prefix 'hexa' means six. The shape appears throughout nature, most famously in the cells of a honeycomb, because it fills space perfectly without leaving gaps.
Correct answer: 30
15% of 200 is 30. An easy way to work it out: 10% of 200 is 20, and 5% is half of that, which is 10. Add them together: 20 + 10 = 30.
Correct answer: A prime number
A prime number has exactly two divisors: 1 and itself. The first prime numbers are 2, 3, 5, 7, 11 and 13. The number 2 is the only even prime in the entire sequence.
Correct answer: 3.14
Pi is approximately 3.14. It represents the ratio of a circle's circumference to its diameter. It is an irrational number, meaning its decimals continue forever without ever repeating.
Correct answer: Pythagoras' theorem
Pythagoras' theorem states that in a right-angled triangle, the square of the hypotenuse equals the sum of the squares of the other two sides. Thales' theorem, by contrast, deals with ratios between parallel lines.
Correct answer: 180 degrees
The angles of a triangle always add up to 180 degrees, whatever its shape. This fundamental rule lets you find a missing angle as soon as you know the other two.
Correct answer: L
In Roman numerals, L stands for 50. Other useful markers: V is 5, X is 10, C is 100, D is 500 and M is 1000. This system was used throughout ancient Rome.
Correct answer: 12
The square root of 144 is 12, because 12 x 12 = 144. A square root is the value that, when multiplied by itself, gives back the original number.
Correct answer: The product
The result of a multiplication is the product. Worth remembering: addition gives a sum, subtraction gives a difference, multiplication gives a product, and division gives a quotient.
Stuck on one, or just curious how nasty it gets? Every hard mode question is here with its answer and the reasoning behind it.
Correct answer: 1,024
1,024, which is why computing memory comes in such odd sizes.
Correct answer: 8
Eight: 2, 3, 5, 7, 11, 13, 17 and 19.
Correct answer: Euclid
Euclid, whose book was used as a textbook for around two thousand years.
Correct answer: -1
-1, which is the whole point of i.
Correct answer: 135 degrees
135 degrees, from (8 - 2) × 180 ÷ 8.
Correct answer: 1
1, by convention, and it keeps the formulas tidy.
Correct answer: 10
10, that is 8 + 2.
Correct answer: An icosahedron
An icosahedron, as any role-player with a d20 will tell you.
Correct answer: e^(iπ) + 1 = 0
e^(iπ) + 1 = 0, often called the most beautiful equation in mathematics.
Correct answer: 5,050
5,050. The young Gauss is said to have worked it out in moments.