| Component | Max | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|
| Overall | 100 | 33 | 48 | 63 | 77 |
| Internal assessment | 20 | 9 | 12 | 15 | 18 |
| Paper 1 | 80 | 25 | 37 | 49 | 61 |
| Paper 2 | 80 | 26 | 37 | 49 | 60 |
SL Paper 1
The paper was accessible and tested many topics; students executed procedures but often misread what was being asked or did not understand what they were finding.
Found difficult
- depreciation
- accuracy instructions
- communicating reasoning
- outliers
- cumulative frequency graphs
- normal distribution
- model limitations
- sketching graphs
- asymptotes
- fair games
- expected value
- trapezium rule
- area between curves
Well prepared
- percentage error
- financial applications on the gdc
- chi-squared test for independence
- perpendicular bisectors
- systems of linear equations
- volume and surface area of 3d shapes
- normal distribution
- quadratic functions
- gdc use
- definite integrals
| Q | Topic | How it went | Where marks were lost |
|---|---|---|---|
| 1 | percentage error and standard form | Answered well | swapped exact and approximate values; gave a negative percentage error; rounded to 3 s.f. when another form was askedTip: Percentage error uses the absolute difference divided by the exact value. |
| 2 | compound interest and depreciation rate | Mixed | ignored the two decimal place instruction; wrong P/Y and C/Y for quarterly compounding; solved for the wrong quantity in the depreciation partTip: Money answers usually need 2 decimal places; set compounding periods per year to match the question. |
| 3 | quartiles from a cumulative frequency curve and outliers | Most struggled | read quartiles on the wrong axis; argued outliers from min and max instead of the 1.5 IQR ruleTip: Read quartiles from the frequency axis at n/4 and 3n/4, then apply the 1.5 IQR fences. |
| 4 | Spearman's rank and Pearson's coefficient | Mixed | used the wrong approach for tied ranks; gave r squared or truncated values; stated strength without direction or context; did not see why Pearson is unsuitableTip: Describe correlation by direction and strength in context; outliers and non-linear data weaken Pearson's r. |
| 5 | mean from a frequency table with an unknown | Most struggled | did not see the total frequency was the answer to (a); could not set up the mean equation; used trial and errorTip: Mean equals sum of f times x over sum of f; set that equal to the given mean and solve. |
| 6 | chi-squared test for independence and conditional probability | Answered well | left fractions unsimplified or above 1; accepted H0 when the statistic exceeded the critical valueTip: Reject H0 when the p-value is below the significance level or the statistic exceeds the critical value. |
| 7 | Voronoi diagram and perpendicular bisector | Mixed | did not show enough work to justify the bisector equation; could not find the intersection of two given lines; too few significant figuresTip: In a show that, write the midpoint, the gradient and its negative reciprocal explicitly. |
| 8 | volume and surface area of an ice cream shape | Mixed | took one fifth of the volume or subtracted 0.2; did not round to 3 s.f.; picked the wrong surface area formulaTip: Break compound shapes into standard solids and match each formula in the booklet carefully. |
| 9 | normal distribution and a symmetric interval | Mixed | answers with no working; only copied the probability statement for the symmetric intervalTip: Use symmetry: a central probability of 0.6 leaves 0.2 in each tail for inverse normal. |
| 10 | quadratic model of a projectile | Mixed | gave the vertex as a pair when only x was asked; misused function notation; could not state limitations of the modelTip: Limitations come from context: think about the domain, negative values and what the model ignores. |
| 11 | sketching a function with an asymptote | Most struggled | sketch not smooth or not approaching the asymptote; gave solutions as coordinates or missed one; could not write the asymptote equationTip: Copy key features from the GDC into the given window and write asymptotes as x = c or y = c. |
| 12 | probability distribution and fair game | Most struggled | did not use that probabilities sum to 1; compared odds instead of computing E(X)Tip: A game is fair when the expected gain E(X) equals zero. |
| 13 | trapezium rule and area of a dam cross-section | Most struggled | used one trapezoid instead of the trapezium rule; wrong number of strips; omitted + c; took the integral alone as the whole areaTip: Count intervals carefully for the trapezium rule and add any extra regions to the integral. |
What to practise
- Show working so method marks can be awarded.
- Read whether a coordinate pair or a single value is required.
- Sketch GDC graphs as part of the working and keep full accuracy until the end.
- Become familiar with the formula booklet.
- Teach students to interpret results and state limitations of real-life models.
SL Paper 2
Results were well spread with some very strong scripts, but parts requiring interpretation or reasoning were consistently weak.
Found difficult
- area of a triangle
- angle properties
- arithmetic sequences
- unit conversion
- standard form
- binomial distribution
- t-test
- meaning of a p-value
- algebraic manipulation
- multiple solutions
Well prepared
- sine and cosine rules
- arithmetic sequences
- geometric sequences and series
- exponential functions
- gdc use
- binomial distribution
- hypothesis testing
- optimisation
| Q | Topic | How it went | Where marks were lost |
|---|---|---|---|
| 1 | triangle trigonometry, area and arc length | Mixed | used right-angled ratios in a non-right triangle; used the wrong angle in the area formula; could not solve the cosine rule equation; used the sector area formula for arc lengthTip: Check whether a triangle is right-angled before using SOH CAH TOA; use the included angle for area. |
| 2 | arithmetic and geometric sequences and series | Mixed | did not switch from term to sum; switched to geometric formulas wrongly; rounded n down so the sum fell short; used 0.05 instead of the right ratioTip: When a total must reach a target, round n up and check the type of sequence each time. |
| 3 | exponential growth of bacteria | Mixed | thought an exponent of 0 gives 0; did not convert hours to minutes; struggled with numbers in standard formTip: Any non-zero base to the power 0 is 1; always check the unit requested in the answer. |
| 4 | binomial distribution and t-test | Mixed | rounded to 2 s.f.; wrong boundaries in binomial cdf; hypotheses that did not cover all cases; did not state the significance level when comparingTip: Write hypotheses with mu, state the level used, and know what the p-value represents. |
| 5 | garden area expressions and optimisation | Most struggled | omitted brackets when multiplying expressions; ignored the given area expression; missed the second set of dimensions; did not use the GDC for the maximumTip: Use given expressions, consider every solution, and check maxima with the GDC graph. |
What to practise
- Teach the reasoning behind topics so students can adapt to new situations.
- Use the GDC solver and graphs instead of solving equations by hand.
- Focus on precise language in hypothesis tests.
- Use the formula booklet regularly in class.
Internal assessment
What moderators raised about the exploration this session, criterion by criterion.
- A. aim different from the title and processes included that do not serve the aim
- A. many graphs stacked before any discussion, and headings without linking explanations
- B. irrelevant charts, formulae shown for GDC results and wrong format for hypothesis tests
- B. unlabelled axes, inconsistent function notation and calculator screenshots
- C. stated interest or effort without engagement in the mathematics, often in template-like work
- D. reflection limited to a closing summary or personal opinion rather than throughout
- E. statistical tests applied without checking assumptions and correlation confused with causation
- E. model parameters from arbitrary points and model choice justified only by R squared
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 2023 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 2023 TZ2?
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The questions most candidates struggled with were on quartiles from a cumulative frequency curve and outliers, mean from a frequency table with an unknown, sketching a function with an asymptote and probability distribution and fair game. The tables above list every question discussed in the report, paper by paper.
What did candidates find difficult in May 2023 TZ2?
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Across the papers the examiners listed depreciation, accuracy instructions, communicating reasoning, outliers, cumulative frequency graphs, normal distribution, model limitations and sketching graphs, among others.
What were the grade boundaries for Maths AI SL May 2023 TZ2?
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Maths AI SL: a 7 from 77 out of 100 overall in May 2023 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.