Published 1 Jul 2026
E-Math Statistics and Probability Mistakes: Tables, Averages, and Counting
A focused guide to common E-Math statistics and probability mistakes, including averages, frequency tables, cumulative frequency, probability, and counting.
Quick answer
Statistics and probability mistakes often come from reading the table wrongly, using the wrong total, or treating averages and probabilities as formula-only tasks.
Key takeaways
- Identify the total and category before calculating.
- Check whether data is raw, grouped, cumulative, or weighted.
- In probability, define the event clearly before counting.
Editorial note
Mentora's E-Math guides use common revision difficulties and Singapore GCE O-Level question patterns. They are practical study support, not a replacement for school guidance or current SEAB requirements.
Read Mentora's methodology and editorial standardsRead the data structure first
Statistics questions can look straightforward, but the table structure matters. Raw data, frequency tables, grouped data, and cumulative frequency need different handling.
Many errors happen before the formula is even chosen.
Common probability traps
Probability mistakes often come from using the wrong denominator, double-counting, or not separating cases clearly.
Students should write the event in words before calculating.
- Check whether replacement is involved.
- Use the correct total after each draw.
- Separate 'and' from 'or' cases.
- Check whether outcomes are equally likely.
Review by mistake type
After marking, classify whether the mistake was table reading, formula choice, arithmetic, or event counting.
That makes the next practice task much clearer than simply doing another mixed statistics set.
More E-Math help
Browse the E-Math resource library.
Find topic guides, free Mistake Finders and paper-practice resources for the problem you have just spotted.
Browse free E-Math resourcesFAQ
Why do I make mistakes in E-Math statistics?
The issue is often reading the table structure wrongly or using the wrong total. Identify the data type before calculating.
How do I improve E-Math probability?
Define the event, count favourable outcomes carefully, check the denominator, and separate multi-step cases before simplifying.
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Published by Mentora · Published 1 Jul 2026
Editorial and source details
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