# Valid arguments and logical fallacies - making sure my homework answers are correct

• Nov 4th 2010, 09:01 AM
turtle27
Valid arguments and logical fallacies - making sure my homework answers are correct

1) Determine whether the reasoning used in (a)-(e) below is inductive or deductive.

(a) Joan plugs her hair dryer in an outlet in the bathroom, bedroom and the
kitchen and discovers it will not work in any of them. She concludes that
there is no electricity coming to her home.

A: inductive

(b) The Chronicle reports that university employees are to receive an average
salary increment of 4%. Since Ken works for the university, his neighbors
conclude he will receive an increment of 4%.

A: deductive

met government standards for airworthiness with its Starship. Thus Starship
will be able to make deliveries to customers by next spring.

A: inductive

(d) In the last 5 years alone, 30,000 patients have received transplanted organs.
Kidney, liver, and heart transplants have become safer, more realistic options
for many patients.

A: inductive

(e) The Chicago markets are o ffering innovative fi nancial high-value fin nancial
products. The New York markets are demanding stricter federal regulations
of the Chicago markets. Federal regulators should say no to this plea for protectionism;
otherwise, the U.S. will lose its edge in financial services.

A:inductive

2) For each of the logical arguments below explain the forms of deductive
reasoning which can be used to reach the conclusion, assuming the premises are
true.

(a) Premises: We shall see a Bugs Bunny classic - either \Falling Hare" or \Rabbit
Seasoning." We did not see \Falling Hare."
Conclusion: We saw \Rabbit Seasoning."

A: "or"

(b) Premises: If it is a low tar cigarette, it claims great taste and less tar. Merit
is a low tar cigarette.
Conclusion: Merit claims great taste and less tar.

A: direct

(c) Premises: Smoking by pregnant women may result in fetal injury, premature
birth, and low birth weight for the child. If a child has low birth rate, it may
not develop as rapidly as other children.
Conclusion: Since Karen smokes, her pregnancy may result in a child which
does not develop as fast as other children.

A: direct

(d) Premises: Wear carpets will not be stained by spilled co ee. Stan's carpet
shows coff ee stains.
Conclusion: Stan's carpet is not a wear carpet.

A: Hint: Change fi rst statement to an `if, then'.
indirect

3) Determine a valid conclusion, which uses all of the statements, for each of
the following list of premises (which are assumed to be true).

(a) If the Vietnamese refugee is not a victim of persecution, the refugee will be
held in a detention camp. The refugee is not held in a detention camp.

A: The vietnamese refugee is not a victim of persecution

(b) All robins have 4 aqua-colored eggs and orange-colored breasts. This bird has
a gray breast.

A: Hint: Change first statement to 'if, then'.
The bird is not a robin.

(c) Either the mosquitoes are out or the caribou range freely. If the mosquitoes
are out, some caribou buck and run in wild desperation. The caribou are not
ranging freely.

A: the mosquitoes are out

(d) If Virginia is a professional airline passenger, she will scrutinize a checklist of
over 100 items. If she is lazy, she will not scrutinize the checklist. Virginia is
lazy.

A: virginia is not a professional airline passenger

12) Determine a valid conclusion which uses all of the statements, for each of
the following lists of premises (which are assumed to be true).

(a) If he is under 20, driving a car is inspiring. If he is not comfortable, driving a
car is not inspiring. If he is comfortable, he will be more relaxed. He is under
20.

A: driving a car is inspiring

(b) Rural pregnant women in poverty often su ffer malnutrition. If a child does not
su ffer a permanent disability or infant mortality, the child did not have a low
birth weight. If a pregnant woman su ffers malnutrition, her child may have a
low birth rate.

A: ????

14) In (a)-(d) below, note the conclusion obtained by assuming the truth of
the set of premises listed and determine if the conclusion is i) valid; ii) invalid; or
iii) there is not enough information to determine whether the conclusion is valid or
invalid.

(a) Premises: All Orangy citric juice comes from Florida. Some Orangy citric
juice contains grapefruit juice. No juice which comes from Florida contains
vitamin supplements. Conclusion: No Orangy citric juice contains vitamin
supplements.

A: invalid

(b) Premises: The same as in (a). Conclusion: Some juices that contains grapefruit
juice do not contain vitamin supplements.

A:valid

(c) Premises: All houses up for sale are too expensive. Some bungalows are up
for sale. Conclusion: Some bungalows are too expensive.

A: valid

18) Sentences (a)-(f) below are taken from general information written by a
tour company. Rewrite each sentence in the forms \if..., then...", \and\, \or", or a
combination of these.

(a) A deposit of \$1,000 per person is required to book on the tour.

A:????

(b) All cancellations of con rmed reservations are subject to a \$100 per person

A: ????

(c) In most cases ticketing changes made after the deadline result in an increase
in airfare.

A: if airfare increased, then john made the ticket changes after the deadline

(d) We cannot accept any responsibility for losses or additional expenses due to
delay or changes in air of other services, sickness, weather, acts of God or other
causes beyond our control.

A: if there are airline delays, changes in air, sickness, weather, acts of God, or other causes beyond our control, then we cannot accept responsibility for losses or additional expenses.

(e) The right is reserved to cancel any tour prior to departure, in which case the
entire payment will be refunded without further obligation on our part.

A: if the right id reserved to cancel any tour prior to our depature, then the entire payment will be refunded without further obligation on our part.
• Nov 4th 2010, 10:14 AM
Ackbeet