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Inference - Advanced Level: probable inference ADVANCED

Quick competitive exam prep session: 20 advanced-level inference questions. Worksheet 27 of 30 - Focus: probable inference. Practice hidden meanings, implicit information, conclusion drawing with instant feedback. Great for advanced students needing complex scenarios and multi-step problems practice.

📝 Worksheet 27 of 30 • 20 questions • ⏱️ Estimated time: 20 minutes • 🎯 Advanced level

What you'll learn in this worksheet:
Your progress through Inference
Worksheet 27 of 30 (90% complete)

Question 1

Analogical reasoning: "A government's budget should be managed like a household budget." What is the most reasonable inference by analogy?
This uses analogical reasoning: A government's budget should be managed like a household budget.

The analogy maps relationships from the source domain to the target domain, suggesting: Governments should avoid deficit spending just as households should

Analogical inferences are suggestive but not logically certain; the strength depends on the relevance and similarity of the mapped features.
analogy, metaphor, mapping

Question 2

Observation: The patient has a fever and cough. Possible diagnoses: common cold, flu, COVID-19, or pneumonia. Which is the most reasonable inference about the cause?
This is abductive reasoning (inference to the best explanation). Given the observation 'The patient has a fever and cough. Possible diagnoses: common cold, flu, COVID-19, or pneumonia.', we consider possible causes and select the most plausible one. The flu is a likely diagnosis (given typical seasonal presentation) is the best explanation because it's the most common, simplest, or most likely cause.
abduction, best-explanation, diagnosis

Question 3

Given these logical premises: • All birds can fly • Penguins are birds but cannot fly • This statement is about typical birds • Tweety is a typical bird Which statement must be true?
This requires multi-step logical deduction:
• All birds can fly
• Penguins are birds but cannot fly
• This statement is about typical birds
• Tweety is a typical bird

Applying logical rules (modus ponens, modus tollens, contrapositive, transitive property, quantifier logic), we can conclude: Tweety can fly
multi-step, quantifier, modal

Question 4

Given: No reptiles are warm-blooded. A snake is a reptile. What can you logically conclude?
This is a direct inference. The conclusion follows necessarily from the premise: "No reptiles are warm-blooded. A snake is a reptile." leads to "A snake is not warm-blooded" because the premise establishes a universal relationship and then confirms the condition.
direct, deductive, modus-ponens

Question 5

Consider these premises: • All roses are beautiful • Some beautiful things are expensive • This is a rose Which conclusion logically follows?
By combining the premises logically:
• All roses are beautiful
• Some beautiful things are expensive
• This is a rose

We can deduce: This is beautiful

This uses 3-step logical reasoning, applying transitive properties and categorical logic.
syllogism, chain-reasoning

Question 6

Rule: If you exercise regularly, you stay healthy Observation: John is not healthy What can you logically infer?
This uses the contrapositive rule. The statement "If you exercise regularly, you stay healthy" is logically equivalent to its contrapositive: 'If NOT consequence, then NOT condition.' Since we observe "John is not healthy" (the consequence is false), we can conclude "John doesn't exercise regularly" (the condition is false).
contrapositive, modus-tollens

Question 7

Statistical information: The probability of rain given dark clouds is 85%. The sky has dark clouds. What is the most reasonable inference?
This is probabilistic reasoning. The statistical evidence (The probability of rain given dark clouds is 85%. The sky has dark clouds.) doesn't guarantee certainty, but it provides strong support for: It will probably rain

Remember: Probability inferences are about likelihood, not certainty.
probabilistic, statistical, likelihood

Question 8

Quantifier logic: • All A are B • Some B are C • No C are D What can be inferred about the relationships?
This tests understanding of quantifiers (all, some, no, most). Some A may be C (but not necessarily)

Remember: 'Some' means 'at least one' (could be all). 'Most' means 'more than half'. No categorical statement about individuals follows from 'most' statements.
quantifiers, all-some-none, logic

Question 9

Consider this argument: "The team won the championship. They must have the best coach." What unstated assumption must be true for this reasoning to be valid?
The argument makes a hidden assumption: Championship wins indicate best coaching (and the coach was the primary factor in the win)

This assumption is not explicitly stated but is necessary for the conclusion to follow from the premises. If this assumption is false, the argument becomes weak or invalid.
assumption, critical-thinking, argument-analysis

Question 10

Statistical finding: Quality control tested 100 products and found 2 defects. The production run has 10,000 items. What can you infer about the population?
This uses statistical inference: from a representative sample, we can make probabilistic claims about the population. Approximately 200 items in the run are defective (based on 2% sample rate) is the appropriate inference, accounting for sampling error and confidence levels.
sampling, generalization, confidence

Question 11

Logical condition: Rain is sufficient for wet ground. The ground is wet. What can you infer?
This tests necessary vs. sufficient conditions.

- If A is SUFFICIENT for B: A → B (A guarantees B, but B can happen without A)
- If A is NECESSARY for B: B → A (B cannot happen without A)

Cannot conclude it rained (could be sprinklers)
necessary-conditions, sufficient-conditions, logic

Question 12

Observation: Traffic accidents decreased by 50% after installing speed cameras What causal inference is most reasonable?
This inference uses temporal precedence (the cause occurred before the effect) and correlation to suggest causation: Speed cameras likely reduced traffic accidents

However, be aware of alternative explanations (confounding variables, regression to the mean, etc.) that might also explain the observation.
causation, temporal, correlation

Question 13

Logical condition: Practice is necessary for mastery. Sarah has mastery. What can you infer?
This tests necessary vs. sufficient conditions.

- If A is SUFFICIENT for B: A → B (A guarantees B, but B can happen without A)
- If A is NECESSARY for B: B → A (B cannot happen without A)

Sarah practiced
necessary-conditions, sufficient-conditions, logic

Question 14

Quantifier logic: • No reptiles have fur • All snakes are reptiles • Some pets are snakes What can be inferred about the relationships?
This tests understanding of quantifiers (all, some, no, most). Some pets do not have fur

Remember: 'Some' means 'at least one' (could be all). 'Most' means 'more than half'. No categorical statement about individuals follows from 'most' statements.
quantifiers, all-some-none, logic

Question 15

Analogical reasoning: "A government's budget should be managed like a household budget." What is the most reasonable inference by analogy?
This uses analogical reasoning: A government's budget should be managed like a household budget.

The analogy maps relationships from the source domain to the target domain, suggesting: Governments should avoid deficit spending just as households should

Analogical inferences are suggestive but not logically certain; the strength depends on the relevance and similarity of the mapped features.
analogy, metaphor, mapping

Question 16

Given these logical premises: • Every cat is a mammal • No mammal can fly • Some pets are cats • Whiskers is a cat Which statement must be true?
This requires multi-step logical deduction:
• Every cat is a mammal
• No mammal can fly
• Some pets are cats
• Whiskers is a cat

Applying logical rules (modus ponens, modus tollens, contrapositive, transitive property, quantifier logic), we can conclude: Whiskers cannot fly
multi-step, quantifier, modal

Question 17

Consider this argument: "Our competitor lowered prices and gained market share. We should lower ours too." What unstated assumption must be true for this reasoning to be valid?
The argument makes a hidden assumption: Lowering prices will increase our market share (and our situation is identical to theirs)

This assumption is not explicitly stated but is necessary for the conclusion to follow from the premises. If this assumption is false, the argument becomes weak or invalid.
assumption, critical-thinking, argument-analysis

Question 18

Logical condition: Being a square is sufficient for being a rectangle. This shape is a square. What can you infer?
This tests necessary vs. sufficient conditions.

- If A is SUFFICIENT for B: A → B (A guarantees B, but B can happen without A)
- If A is NECESSARY for B: B → A (B cannot happen without A)

It is a rectangle
necessary-conditions, sufficient-conditions, logic

Question 19

Given these logical premises: • If P, then Q • If Q, then R • If R, then S • Not S Which statement must be true?
This requires multi-step logical deduction:
• If P, then Q
• If Q, then R
• If R, then S
• Not S

Applying logical rules (modus ponens, modus tollens, contrapositive, transitive property, quantifier logic), we can conclude: Not P
multi-step, quantifier, modal

Question 20

Analogical reasoning: "Birds build nests for their young. Bees build hives." What is the most reasonable inference by analogy?
This uses analogical reasoning: Birds build nests for their young. Bees build hives.

The analogy maps relationships from the source domain to the target domain, suggesting: Bees build hives for their young (the hive serves the same protective function as a nest)

Analogical inferences are suggestive but not logically certain; the strength depends on the relevance and similarity of the mapped features.
analogy, metaphor, mapping
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