| Component | Max | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|
| Overall | 100 | 27 | 40 | 53 | 66 |
| Internal assessment | 20 | 9 | 12 | 15 | 18 |
| Paper 1 | 80 | 19 | 29 | 40 | 50 |
| Paper 2 | 80 | 19 | 29 | 38 | 48 |
SL Paper 1
A paper with mixed difficulty; GDC users outperformed those using longer manual methods, while probability distributions, bearings and bounds were weak.
Found difficult
- probability distributions
- expected value
- conditional probability
- bearings
- upper and lower bounds
- inverse functions
Well prepared
- financial applications on the gdc
- geometric sequences and series
- chi-squared test for independence
- voronoi diagrams
- sine and cosine rules
- 3d coordinate geometry
| Q | Topic | How it went | Where marks were lost |
|---|---|---|---|
| 1 | loan and savings with the finance app | Mixed | used compound interest formula with non-zero PMT; swapped PV and PMT; ignored the bold two decimal place instructionTip: Use the TVM solver whenever regular payments occur, and follow rounding instructions exactly. |
| 2 | discrete probability distribution, expectation and conditional probability | Most struggled | assumed all outcomes equally likely; used E(X) = np for a non-binomial table; ignored the given condition of an odd outcomeTip: E(X) is the sum of x times P(X = x); np only applies to binomial variables. |
| 3 | geometric sequence of ant numbers | Mixed | gave non-integer counts; listed terms instead of using the formula; treated it as arithmetic; rounded 20.4 weeks up instead of downTip: Think about context when rounding: whole items and completed weeks may need rounding down. |
| 4 | chi-squared test for independence | Answered well | incorrect null hypothesis; wrong conclusion from a correct p-valueTip: H0 states that the variables are independent; reject it only when p is below the significance level. |
| 5 | bearings with the cosine rule | Most struggled | assumed a right angle or isosceles triangle; used the sine rule without enough information; could not convert to a bearingTip: With two sides and the included angle, use the cosine rule; then measure the bearing clockwise from north. |
| 6 | bounds of a measured time and speeding | Most struggled | did not find bounds of the rounded time; gave a one-word conclusion for a six-mark questionTip: Use the extreme bounds to test whether a conclusion is certain; let the marks guide how much to write. |
| 7 | Voronoi boundary and vertices | Mixed | found the line through the sites instead of its perpendicular bisector; did not use the known x-coordinate to get yTip: A boundary between two sites is their perpendicular bisector, not the line joining them. |
| 8 | cumulative frequency curve and estimated mean | Mixed | found the percentage below rather than above the limit; did not use class midpoints; divided by 100 instead of 80Tip: Estimate a grouped mean with midpoints and divide by the actual total frequency. |
| 9 | function notation and inverse from a table | Most struggled | read f^-1 as the derivativeTip: f^-1(x) is the inverse function: swap the roles of input and output in the table. |
| 10 | Spearman's rank correlation of judges | Most struggled | read the dog labels A, B, C as ranks; commented only 'positive and strong' without reference to ranksTip: Check what labels mean before ranking, and interpret Spearman's value in terms of agreement of ranks. |
| 11 | 3D coordinate geometry | Mixed | later parts left unansweredTip: Distance in 3D is the square root of the sum of the three squared differences; keep going to later parts. |
What to practise
- Read instructions carefully, especially rounding requirements.
- Show working: marks are not given for a correct answer reached by a wrong method.
- Present one solution only and cross out alternatives.
- Use the mark allocation to judge how much explanation is needed.
- Practise from a variety of past and specimen papers.
SL Paper 2
A challenging paper on which many scored under half marks; students often gave up after early parts and lost marks on simplification and show that parts.
Found difficult
- simplifying answers
- unfamiliar contexts
- graphing derivatives
- variance
- binomial distribution
- multi-step probability
- sinusoidal models
- show that questions
Well prepared
- arithmetic sequences
- gdc use
- area under a curve
- normal distribution
- pythagoras theorem
- volume and surface area of 3d shapes
| Q | Topic | How it went | Where marks were lost |
|---|---|---|---|
| 1 | arithmetic sequences in a patterned cushion | Mixed | unsure which value is u1; did not simplify the sum expression; counted only the bottom layerTip: Identify the first term carefully and simplify general expressions fully. |
| 2 | intersections, area between curves and derivative graphs | Mixed | found only one intersection with the solver; gave coordinates when x-values were asked; could not graph derivatives on the GDCTip: Graph both functions to see all intersections, and learn to plot a numerical derivative on the GDC. |
| 3 | normal distribution of times, variance and binomial | Most struggled | misread the defined variable so used the wrong mean; rounded an expected count to an integer; forgot to add 10 and give a clock time; used 1 instead of 0 as lower boundTip: Reread how X is defined, and convert your answer back into the form the context needs. |
| 4 | clock hands geometry and sinusoidal height model | Most struggled | used arc length for a straight distance; wrong values for the parameters; invented numbers in a show that; did not give time to the nearest minuteTip: Link the period and amplitude to the physical motion, and give times in the requested format. |
| 5 | surface area minimisation of a cylinder with hemisphere | Most struggled | did not simplify surface area or volume expressions; could not rearrange for h; did not substitute h into the area; few found h after rTip: In show that chains, substitute the previous given result and simplify step by step to reach the target. |
What to practise
- Express fractions with integer numerator and denominator in lowest terms.
- Explain how a show that is built and never use the target value in it.
- Use given show that results in later parts.
- Practise long mixed-topic contextual questions.
- Budget time so every question is attempted.
Internal assessment
What moderators raised about the exploration this session, criterion by criterion.
- A. several aim-like statements and unneeded plan or methodology sections reduce focus
- A. headings used without linking ideas, and conclusion not matching the aim
- B. calculator notation, inconsistent variables and missing approximately-equal sign when rounding
- B. imprecise wording in chi-squared hypotheses and unexplained screenshots or regression lines
- C. engagement equated with effort or interest rather than independent mathematical thinking
- D. conclusions based on personal assumptions and reflection only at the end
- E. a fixed list of statistical processes applied regardless of the data's features
- E. models chosen only by R squared, and Voronoi diagrams drawn but not interpreted
About this summary
After every session the IB sends schools a subject report: how candidates did on each paper and question, and what teachers should work on. This page is my reading of the Maths AI SL report for May 2025 TZ2, in my own words. No text from the report or from the exam questions is reproduced, and it is not endorsed by the International Baccalaureate.
Session codes: TZ is the time zone variant of the papers. Other variants of the same session:
Frequently asked questions
Which questions were hardest in Maths AI SL May 2025 TZ2?
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The questions most candidates struggled with were on discrete probability distribution, expectation and conditional probability, bearings with the cosine rule, bounds of a measured time and speeding and function notation and inverse from a table. The tables above list every question discussed in the report, paper by paper.
What did candidates find difficult in May 2025 TZ2?
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Across the papers the examiners listed probability distributions, expected value, conditional probability, bearings, upper and lower bounds, inverse functions, simplifying answers and unfamiliar contexts, among others.
What were the grade boundaries for Maths AI SL May 2025 TZ2?
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Maths AI SL: a 7 from 66 out of 100 overall in May 2025 TZ2. The component boundaries are in the table on this page.
Is this the official IB subject report?
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No. It is my summary of the report the IB issues to schools after each session, rewritten in my own words with a teacher's reading of it. No text from the report or from exam questions is reproduced. Your school's IB coordinator can access the original.