Critical thinking: guide and free practice

Critical thinking practice helps you distinguish facts, assumptions and conclusions, and judge whether evidence genuinely supports an argument.

Five skills to separate

Inference asks what the evidence supports. Assumption questions ask what an argument takes for granted. Deduction asks what must follow. Interpretation asks whether a conclusion is justified by the data. Argument evaluation asks whether a reason is relevant and substantial for the decision.

Challenge the bridge

A recommendation often jumps from an observation to an action. Identify the missing bridge. If a firm proposes an app to reduce queues, it assumes enough people can and will use the app. It does not need to assume everyone owns the newest phone.

Correlation is a starting point

When trained staff make fewer errors, training may help, but selection and experience could also explain the difference. Ask what comparison would distinguish the explanations. A larger sample does not automatically fix a biased comparison.

Provider context

TalentLens describes Watson-Glaser as covering inference, assumptions, deduction, interpretation and argument evaluation. Our original set introduces those skills using four-option teaching questions; it does not reproduce its scoring scales or item formats. Provider information was checked on 22 October 2026. Use the official practice resource for format familiarisation.

Your first practice session

Select the best-supported conclusion or evaluation for the precise question. These teaching items use four options, not official Watson-Glaser response scales.

Try 10 questions with explanations

Worked examples

  1. 1. A cafe proposes mobile ordering to reduce its counter queue. Which assumption is necessary for that proposal to reduce the queue through mobile ordering?
    1. Enough customers will use mobile ordering instead of ordering at the counter
    2. Every customer has a new phone
    3. The cafe will double its prices
    4. All staff prefer mobile apps

    Reference: q-b095775a-154 · Report this question

    Show answer and solution

    Answer: A. Enough customers will use mobile ordering instead of ordering at the counter

    The proposed mechanism needs some counter orders to shift to mobile. It does not require universal adoption or a particular phone model.
  2. 2. A survey of 30 volunteers from a cycling club finds 90% cycle to work. What is the strongest objection to using this as the city commuting rate?
    1. Thirty is an odd number
    2. Cycling-club volunteers may not represent city commuters
    3. Percentages cannot describe transport
    4. Volunteers always lie

    Reference: q-fdcd9c1b-145 · Report this question

    Show answer and solution

    Answer: B. Cycling-club volunteers may not represent city commuters

    The sample is selected from a group particularly likely to cycle, so it can be biased even if every response is accurate.
  3. 3. Staff who took an optional course had a lower recorded error rate than staff who did not. What cannot yet be concluded?
    1. The groups had different error rates
    2. The course caused the lower error rate
    3. A course was offered
    4. Some staff took the course

    Reference: q-6f67fa2a-120 · Report this question

    Show answer and solution

    Answer: B. The course caused the lower error rate

    The recorded rates differ, but prior ability, motivation or experience could explain that difference. Observed association alone does not establish that the course caused it.

Continue learning

Source and independence

TalentLens critical-thinking guidance. Provider information checked on 22 October 2026. These are independently written learning materials; APTITUDE TESTER is not affiliated with or endorsed by the provider. Our practice scores are not official scores, percentiles or validated hiring predictions.