The accepted answer is great, but I would like to add a little bit on 'numeracy' tests, aptitude tests or assessments and how you might approach them as a candidate.
The term 'numeracy' refers to a broad class of tests. Unless otherwise specified, they should be performed without technical aids (calculators and such). Often times, you are allowed pen and paper to make notes. Tests usually involve some sort of time limit, for example:
- They may limit the amount of time you can spend on each individual question, simulating numerical reasoning under pressure.
- Or they give you a set timespan, in which you have to answer as many questions correctly as possible. Your skill level is determined by the number of questions that you can answer correctly within the time limit. Some tests prioritize accuracy over speed by penalizing incorrect answers.
- Or you do not get a timespan, but the testing tool assigns you incrementally more difficult questions until you start taking too long or start failing consistently.
These tests are heavily susceptible to both training effects and cross-training effects. Training yourself on even a few sample questions of a test increases your performance (relative to untrained individuals of a similar base skill level). However, I would recommend that you do a few questions of many tests rather dan doing many questions of a single test. The testing market is large and methodology varies by testing company.
This is where cross-training comes in: Your confidence in your ability to read, correctly interpret and execute the instructions of a 'new' numeracy test will help your performance more than any sort of test-specific training.
Some example queries that may help you find practice questions:
- Mental Arithmetic, Basic Numeracy
- Number Sequences
- Data Interpretation, Graph Interpretation
- Numerical Estimation
- Combine with: Aptitude, Assessment or test.
Keywords on the same line indicate that I'd expect these to be used interchangeably. For coding interviews, you could also look at Verbal Reasoning, Logical Reasoning and Spatial Reasoning. These are often part of Abstract Reasoning tests.
There is a huge market for training packages for all kinds of aptitude tests. In my personal opinion and experience, this is a huge scam. Most tests are norm-referenced, meaning that candidates are compared to a population average. If you have a degree in a somewhat mathematically inclined field (CS/AI, statistics, econometry/finance, physics), you are likely to score in the top 20% on a bad day, without any preparation. You need to massively increase your raw test score to reach top 5%.
I think you shouldn't train too much: Occasionally someone managed to get a degree and makes a half-decent impression during the in-person interview, despite being utterly incapable of reasoning effectively about simple abstract or numerical concepts. I have yet to meet an otherwise good candidate who flunks the assessment. Differences in tests scores between candidates never influenced a hiring decision I was involved in. At my current and past employers (in the Netherlands), aptitude tests are only used to ensure that candidates meet a reasonable skill floor.