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Math Quiz Questions and Answers

40 math questions with answers: arithmetic, fractions, geometry, famous numbers and the people behind them.

40 questions · tap “Show answer” under each one · Answer key

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Round 1

  1. How many prime numbers are there below 100?

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    25

    There are 168 below 1,000. Source

  2. What is the square root of 144?

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    12

    144, or 12 dozen, is also called a gross. Source

  3. What is the only even prime number?

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    2

    Every other even number can be divided by 2. Source

  4. The three angles of a triangle add up to how many degrees?

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    180

    That holds on a flat surface; on a sphere the angles add up to more. Source

  5. How many sides does the UK's 50p coin have?

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    7

    Its sides are curved, so it has the same width in every direction. Source

  6. The number pi begins with which digits?

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    3.14

    Pi is a circle's circumference divided by its diameter. Source

  7. What is 20% of 150?

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    30

    10% of 150 is 15, so 20% is twice that. Source

  8. What is a number that divides another exactly, as 3 does 12, called?

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    A factor

    12 is a multiple of 3; 3 is a factor of 12. Source

  9. What is 0! (zero factorial)?

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    1

    It's defined as 1, so the formulas for counting arrangements still work. Source

  10. What is 15 × 15?

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    225

    A shortcut for squares ending in 5: 1 × 2 = 2, then append 25 → 225. Source

Round 2

  1. How many faces does a cube have?

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    6

    Each of its faces is a square. Source

  2. What is a shape with all sides equal and all angles equal called?

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    A regular polygon

    A square and an equilateral triangle are both regular. Source

  3. A right triangle has legs of 3 and 4. How long is its longest side?

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    5

    By Pythagoras: 3² + 4² = 9 + 16 = 25, and 25 = 5². Source

  4. Which formula gives the area of a circle?

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    πr²

    2πr is the circumference; 4πr² is the surface of a sphere. Source

  5. What is the next prime number after 7?

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    11

    9 isn't prime: it's 3 × 3. Source

  6. A googol is 1 followed by how many zeros?

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    100

    The name Google is a play on the word. Source

  7. Which of these numbers is neither prime nor composite?

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    1

    A prime has exactly two divisors; 1 has only one. Source

  8. What is 2 to the power of 10?

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    1,024

    That's why a kilobyte was long counted as 1,024 bytes. Source

  9. What is 1,000 ÷ 8?

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    125

    Halve 1,000 three times: 500, 250, 125. Source

  10. What is the mean (average) of 2, 4 and 9?

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    5

    (2 + 4 + 9) ÷ 3 = 15 ÷ 3 = 5. Source

Round 3

  1. What do you get if you add up all the whole numbers from 1 to 100?

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    5,050

    It's 100 × 101 ÷ 2; the story goes that the young Carl Friedrich Gauss saw it at once. Source

  2. How many sides does a stop sign have in most countries?

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    8

    Its unusual shape lets drivers recognize it even from behind. Source

  3. What is an angle of more than 90° but less than 180° called?

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    Obtuse

    Acute is less than 90°; reflex is more than 180°. Source

  4. What is 3 cubed (3³)?

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    27

    3 × 3 × 3 = 27. Source

  5. How do you write the number 5 in binary?

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    101

    One four, no twos and one one: 4 + 1. Source

  6. A triangle with exactly two equal sides is called what?

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    Isosceles

    All three sides equal: equilateral; none equal: scalene. Source

  7. Which Greek mathematician wrote 'Elements', the classic geometry textbook?

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    Euclid

    It was used to teach geometry for more than 2,000 years. Source

  8. In which country did mathematicians first treat zero as a number in its own right?

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    India

    Brahmagupta set out rules for calculating with zero in 628 AD. Source

  9. Which Welsh mathematician introduced the equals sign (=) in 1557?

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    Robert Recorde

    He chose two parallel lines because 'no two things can be more equal'. Source

  10. A square has sides of 5 cm. What is its perimeter?

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    20 cm

    Its area would be 25 cm². Source

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Round 4

  1. How many minutes are there in a week?

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    10,080

    7 days × 24 hours × 60 minutes. Source

  2. Pi Day is celebrated on which date?

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    March 14

    Written month first, it's 3/14. Source

  3. Which symbol stands for infinity?

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    ∞

    John Wallis introduced it in 1655. Source

  4. The word "percent" comes from Latin. What does it mean?

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    Per hundred

    So 40 percent means 40 out of every 100. Source

  5. A circle's radius is 5 cm. How long is its diameter?

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    10 cm

    The diameter is twice the radius. Source

  6. What is the largest prime number with two digits?

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    97

    91 looks prime, but it's 7 × 13. Source

  7. The four angles of any quadrilateral add up to how many degrees?

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    360

    A diagonal splits it into two triangles of 180° each. Source

  8. Which of these numbers is a perfect square?

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    49

    7 × 7 = 49. Source

  9. Which fraction is equal to 0.75?

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    3/4

    0.75 is 75 hundredths, which simplifies to 3/4. Source

  10. The golden ratio is roughly which number?

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    1.618

    3.142 is pi, 2.718 is e and 1.414 is the square root of 2. Source

Answer key

Round 1

  1. 25
  2. 12
  3. 2
  4. 180
  5. 7
  6. 3.14
  7. 30
  8. A factor
  9. 1
  10. 225

Round 2

  1. 6
  2. A regular polygon
  3. 5
  4. πr²
  5. 11
  6. 100
  7. 1
  8. 1,024
  9. 125
  10. 5

Round 3

  1. 5,050
  2. 8
  3. Obtuse
  4. 27
  5. 101
  6. Isosceles
  7. Euclid
  8. India
  9. Robert Recorde
  10. 20 cm

Round 4

  1. 10,080
  2. March 14
  3. ∞
  4. Per hundred
  5. 10 cm
  6. 97
  7. 360
  8. 49
  9. 3/4
  10. 1.618

Link to this page

Sources

  1. en.wikipedia.org/wiki/Prime number
  2. en.wikipedia.org/wiki/Square root
  3. en.wikipedia.org/wiki/Triangle
  4. en.wikipedia.org/wiki/Fifty pence (British coin)
  5. en.wikipedia.org/wiki/Pi
  6. en.wikipedia.org/wiki/Percentage
  7. en.wikipedia.org/wiki/Divisor
  8. en.wikipedia.org/wiki/Factorial
  9. en.wikipedia.org/wiki/Square number
  10. en.wikipedia.org/wiki/Cube
  11. en.wikipedia.org/wiki/Regular polygon
  12. en.wikipedia.org/wiki/Pythagorean theorem
  13. en.wikipedia.org/wiki/Area of a circle
  14. en.wikipedia.org/wiki/Googol
  15. en.wikipedia.org/wiki/Power of two
  16. en.wikipedia.org/wiki/Division (mathematics)
  17. en.wikipedia.org/wiki/Arithmetic mean
  18. en.wikipedia.org/wiki/Triangular number
  19. en.wikipedia.org/wiki/Stop sign
  20. en.wikipedia.org/wiki/Angle
  21. en.wikipedia.org/wiki/Cube (algebra)
  22. en.wikipedia.org/wiki/Binary number
  23. en.wikipedia.org/wiki/Isosceles triangle
  24. en.wikipedia.org/wiki/Euclid's Elements
  25. en.wikipedia.org/wiki/0
  26. en.wikipedia.org/wiki/Equals sign
  27. en.wikipedia.org/wiki/Perimeter
  28. en.wikipedia.org/wiki/Week
  29. en.wikipedia.org/wiki/Pi Day
  30. en.wikipedia.org/wiki/Infinity
  31. en.wikipedia.org/wiki/Diameter
  32. en.wikipedia.org/wiki/Quadrilateral
  33. en.wikipedia.org/wiki/Decimal
  34. en.wikipedia.org/wiki/Golden ratio

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