Logic Questions and Answers

Answer: D

The negation is Amit does not live in Delhi or Aman lives in Mumbai.

The statement has the form 'p and not q', where p is 'Amit lives in Delhi' and q is 'Aman lives in Mumbai'. By De Morgan's law the negation of 'p and not q' is 'not p or q'.

So the 'and' becomes 'or', the first part is negated, and the second part loses its 'not': Amit does not live in Delhi, or Aman lives in Mumbai.

The options keeping 'and' fail because negation swaps 'and' for 'or'. The option with 'Aman does not live in Mumbai' forgot to negate the second part.

Answer: B

The best example is Valerie, who has stopped paying the rent.

Violating a lease means doing something the signed lease forbids. Valerie agreed in writing to pay the monthly rent and has not paid it for three months, so she is in breach of the lease.

Tim only declines to renew, which is his right when the lease ends. Mark merely lists complaints, and Leslie only asks an attorney for advice. None of them breaks a term of the lease.

Answer: A

The best example is Jake, who offers to pay for the repair.

Restitution is compensating someone for damage you caused to their property. Jake damaged Leslie's camera lens through his own carelessness and promises to pay for the repair.

Rebecca only apologises for returning the car with little fuel and offers no compensation. Aaron's friend Tom finds damage he did not cause and calls a plumber, which is not compensation for damage he did. Lisa only suspects the company is to blame and asks it to pay, so she is not the one repairing her own damage.

Answer: D

The best example is Theo, who guesses why Emily is in tears.

Speculation is assuming something is true on inconclusive evidence. Theo sees tears and guesses a death in the family, without any proof.

Francine acts on a written policy, so her evidence is not inconclusive. Mary only regrets her choice of transport. Jennifer is confident after consulting several guidebooks and her agent, which is conclusive enough evidence, not a guess.

Answer: D

The best example is Lori's coworker, who promises a refund if the camera is not of the highest quality.

A guarantee is a promise about the quality of a product, given in writing or verbally by the person selling it. The coworker is the seller and promises her money back if the camera does not perform, which is exactly that.

Melissa's DVD player has high ratings but no promise. Curt is only advised to look for a guarantee. The auto body shop merely specialises in used cars. None of these makes a promise about quality.

Answer: B

The best example is the realtor.

Embellishing the truth is adding fictitious details or exaggerating facts. A house eleven blocks from the ocean is not waterfront, so calling it prime waterfront property exaggerates.

Isabel is giving an opinion about a play. Fred has taught for ten years, so calling himself very experienced is fair. The coach only states a likelihood. None of these invents or inflates a fact.

Answer: B

The keyed reason is that contaminated Ganga water can spread contagious disease.

The Ganga receives large volumes of untreated sewage and industrial effluent, and millions of people bathe in it and use its water. Polluted river water spreads water-borne diseases such as cholera, typhoid and diarrhoea, which is the public-health reason for the clean-up programme (Namami Gange).

The river's religious importance and tourism are real but are not the rationale for pollution control. 'Groundwater cannot be used for drinking' is false as a general statement and is not why the Ganga is being cleaned.

Answer: B

The keyed reason is that hotel food is unhygienic and very spicy.

The statement says home food is always the better choice. The reason that supports this on health grounds is that restaurant food is often prepared with less control over hygiene and with more oil and spice than home cooking.

Expense alone is not a reason to call home food better for you. 'Tasty and full of nutrition' would argue for hotel food, not against it, so 'All of the above' cannot be right either.

Answer: C

True justified belief is often called Knowledge.

The classical definition of knowledge, going back to Plato's Theaetetus, is justified true belief: a person knows something if they believe it, it is true, and they have good reason for believing it. Edmund Gettier's examples of 1963 later questioned whether these three conditions are enough.

A hypothesis is a proposed explanation still to be tested, so it need not be true or justified. Intelligence is a mental capacity, not a kind of belief.

Answer: C

The distance between P and R is less than or equal to x + y.

Going from P to R through Q covers x + y km, and a direct route can never be longer than a route through an intermediate point. This is the triangle inequality: PR ≤ PQ + QR. Equality holds only when Q lies on the straight line between P and R.

The distance is not always exactly x + y, because Q need not lie between P and R, and it can never be greater than x + y. Since 'less than or equal to x + y' is always true, 'None of the above' is wrong too.