1.3 Geometric sequences and series questions for IB Maths AA

60 questions on Geometric sequences and series, written by Augment in the style of IB exam papers. Six of them are below in full, to answer on paper.

  • IB Mathematics: Analysis and Approaches
  • Part of 1 Number and algebra
  • SL and HL

Questions by paper and level

SL and HL questions are for students at either level. HL only questions cover what only HL students study.

PaperSL and HLHL onlyAll
Paper 121526
Paper 231334
Every paper52860

Counted on

Questions to try

Written by Augment in the style of IB exams, not past papers. Answer them on paper, then check each one against its markscheme with a free account.

Question 1 · AA-00685Paper 1 · 5 marks

In a geometric sequence, the second term is 12 and the fifth term is −32.

  1. (a)

    Find the common ratio.

    3 marks

  2. (b)

    Find the sum to infinity of the sequence.

    2 marks

Question 2 · AA-00426Paper 2 · 15 marks

Asha and Bruno play a game in which they take turns to throw a dart at a small target, with Asha throwing first. The first player to hit the target wins and the game stops.

Each time Asha throws, the probability that she hits the target is 0.3. Each time Bruno throws, the probability that he hits the target is 0.4. All throws are independent.

  1. (a)

    Find the probability that Bruno wins with his first throw.

    2 marks

  2. (b)

    Show that the probability that Asha wins with her nth throw is 0.3×0.42 n−1.

    3 marks

  3. (c)

    Find the probability that Asha wins the game.

    3 marks

  4. (d)

    Given that the game ends within the first three throws, find the probability that Asha wins.

    4 marks

  5. (e)

    Find the least number of throws, n, such that the probability that the game lasts for more than n throws is less than 0.01.

    3 marks

Question 3 · AA-00686Paper 1 · 5 marks

Consider the recurring decimal 0.2454545…, in which the digits 45 repeat indefinitely.

  1. (a)

    Write 0.0454545… as the sum of an infinite geometric series, stating its first term and its common ratio.

    2 marks

  2. (b)

    Hence, write 0.2454545… as a fraction in its simplest form.

    3 marks

Question 4 · AA-00687Paper 2 · 6 marks

The sum to infinity of a geometric series is 250. The sum of the first four terms of the series is 140.

  1. (a)

    Show that r4=0.44, where r is the common ratio.

    2 marks

  2. (b)

    Find the two possible values of the first term of the series.

    4 marks

Question 5 · AA-00688Paper 1 · 6 marks

Consider the infinite geometric series

∑k=0∞(2x−35)k,x∈R.
  1. (a)

    Find the values of x for which the series converges.

    3 marks

  2. (b)

    The sum to infinity of the series is 54. Find the value of x.

    3 marks

Question 6 · AA-00690Paper 2 · 6 marks

The bob of a pendulum is released and swings freely. On its first swing, the bob travels along an arc of length 40 cm. On each subsequent swing, the length of the arc is 92% of the length of the arc on the previous swing.

  1. (a)

    Find the length of the arc on the sixth swing.

    2 marks

  2. (b)

    Assuming that the bob swings indefinitely, find the total distance that the bob travels.

    2 marks

  3. (c)

    Find the total distance that the bob travels from the end of its tenth swing onwards.

    2 marks

Practice all 60 in Augment

Free with an account. Every question has its markscheme, and Augment keeps the ones you got wrong so you can come back to them.

The notes on 1.3 Geometric sequences and series

More questions in Number and algebra

  1. 1.1Scientific notation
  2. 1.2Arithmetic sequences and series
  3. 1.3Geometric sequences and seriesThis page
  4. 1.4Financial applications of geometric sequences
  5. 1.5Exponents and introduction to logarithms
  6. 1.6Simple deductive proof
  7. 1.7Laws of exponents and logarithms
  8. 1.8Infinite geometric series
  9. 1.9The binomial theorem
  10. 1.10Counting principles and the extended binomial theoremHL only
  11. 1.11Partial fractionsHL only
  12. 1.12Complex numbers in Cartesian formHL only
  13. 1.13Polar and Euler formHL only
  14. 1.14Complex roots and De Moivre’s theoremHL only
  15. 1.15Proof by induction, contradiction and counterexampleHL only
  16. 1.16Systems of linear equationsHL only

Check your answers in Augment

A free account opens all 60 questions on Geometric sequences and series with their markschemes, and keeps a record of what you have marked.