Assumption and Conclusion Reasoning Questions

1. If it's a weekday, the library is open. The library is open today. Therefore, it must be a weekday. This reasoning is:

Deductive

Inductive

Abductive

Fallacious

2. A company claims that their new energy-efficient light bulbs last 50% longer than traditional bulbs. Which of the following, if true, would most weaken this claim?

The energy-efficient bulbs cost more than traditional bulbs

The company's testing was done under ideal laboratory conditions

Consumers report no significant difference in bulb lifespan in real-world use

The energy-efficient bulbs use less electricity than traditional bulbs

3. No reptiles have fur. Some animals have fur. Therefore, some animals are not reptiles. This argument is:

Valid

Sound

Invalid

Both valid and sound

4. A marketing manager notices that customers who use the company's mobile app make more frequent purchases. She concludes that promoting the app will increase overall sales. Which of the following, if true, would most weaken this conclusion?

The app offers exclusive discounts not available to non-app users

Customers who make frequent purchases are more likely to download the app

The app is only available on certain smartphone platforms

The company's competitors also have mobile apps

5. A city planner proposes building more parks to improve residents' quality of life. Which of the following, if true, would most strengthen this proposal?

Studies show that access to green spaces reduces stress and improves mental health

The city has a budget surplus this year

Some residents have complained about the lack of parking spaces

The city's population is expected to grow in the coming years

6. A company claims that their new air purifier removes 99.9% of airborne particles. Which of the following, if true, would most strengthen this claim?

The air purifier uses a technology patented by the company

Independent laboratory tests confirm the 99.9% removal rate

The air purifier is more expensive than competing models

The company has been manufacturing air purifiers for many years

7. If you eat junk food, you'll gain weight. You've gained weight. Therefore, you must have eaten junk food. This reasoning is:

Modus ponens

Modus tollens

Affirming the consequent

Denying the antecedent

8. All metals conduct electricity. Gold conducts electricity. Therefore, gold is a metal. This argument is:

Valid

Sound

Invalid

Both valid and sound

9. A company introduces a new customer loyalty program and sees an increase in repeat business. The marketing director concludes that the loyalty program is responsible for the increase. Which of the following, if true, would most weaken this conclusion?

The company also improved its product quality during the same period

Competitors have similar loyalty programs

Only a small percentage of customers have joined the loyalty program

The increase in repeat business is consistent across all customer segments

10. A study finds that people who meditate regularly report lower levels of stress. The researchers conclude that meditation reduces stress. Which of the following, if true, would most strengthen this conclusion?

Participants' cortisol levels (a stress hormone) decreased after beginning a meditation practice

People who are less stressed are more likely to try meditation

The study was conducted over a short period of time

Participants in the study were all experienced meditators