1. Which of the following is logically equivalent to "Mariam writes only if she has time"?
2. Which of the following is not logically equivalent to "Mariam writes only if she has time"?
3. Jonathan says, "I will pass the course only if I get 70% or better on the final exam." Jonathan received 75% on the final exam. Did he pass the course?
1. Which of the following is logically equivalent to "Mariam writes only if she has time"?
You answered:
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If Mariam writes then she has time.
In the Introduction to "only if" conditionals, you read that P only if Q is equivalent to If P then Q. In this case, "Mariam writes (p) only if she has time (q )" is equivalent to "If Mariam writes (p), then she has time (q)."
2. Which of the following is not logically equivalent to "Mariam writes only if she has time"?
You answered:
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If she has time, then Mariam writes.
In the Introduction to "only if" conditionals, you read that P only if Q is equivalent to If P then Q. In this case, "Mariam writes (p) only if she has time (q )" is equivalent to "If Mariam writes (p), then she has time (q)." The only option that is not logically equivalent is, "If she has time (q), then Mariam writes (p)."
3. Jonathan says, "I will pass the course only if I get 70% or better on the final exam." Jonathan received 75% on the final exam. Did he pass the course?
You answered:
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Unknown.
"I will pass the course only if I get 70% or better on the final exam" is equivalent to "If I pass the course, then I got 70% or better on the final exam." So the argument is:
If I pass then I got 70%+ | --or-- | If P then Q |
1. Which of the following is logically equivalent to "Mariam writes only if she has time"?
You answered:
-
Mariam writes if she has time.
In the Introduction to "only if" conditionals, you read that P only if Q is equivalent to If P then Q. In this case, "Mariam writes (p) only if she has time (q )" is equivalent to "If Mariam writes (p), then she has time (q)."
1. Which of the following is logically equivalent to "Mariam writes only if she has time"?
You answered:
-
If she has time, then Mariam writes.
In the Introduction to "only if" conditionals, you read that P only if Q is equivalent to If P then Q. But your answer made it If Q then P: "If she has time(q), then Mariam writes (p)."
1. Which of the following is logically equivalent to "Mariam writes only if she has time"?
You answered:
-
Only Mariam writes if she has time.
In the Introduction to "only if" conditionals, you read that P only if Q is equivalent to If P then Q. In this case, "Mariam writes (p) only if she has time (q )" is equivalent to "If Mariam writes (p), then she has time (q)."
2. Which of the following is not logically equivalent to "Mariam writes only if she has time"?
You answered:
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Mariam has time if she writes.
In the Introduction to "only if" conditionals, you read that P only if Q is equivalent to If P then Q. In this case, "Mariam writes (p) only if she has time (q )" is equivalent to "If Mariam writes (p), then she has time (q)." Your answer is another form of that, "Mariam has time (q), if she writes (p)."
2. Which of the following is not logically equivalent to "Mariam writes only if she has time"?
You answered:
-
If Mariam writes, then she has time.
In the Introduction to "only if" conditionals, you read that P only if Q is equivalent to If P then Q. In this case, "Mariam writes (p) only if she has time (q )" is equivalent to "If Mariam writes (p), then she has time (q)." Your answer was exactly that, but you are looking for the option that is not equivalent.
2. Which of the following is not logically equivalent to "Mariam writes only if she has time"?
You answered:
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Mariam only writes if she has time.
In the Introduction to "only if" conditionals, you read that P only if Q is equivalent to If P then Q. In this case, "Mariam writes (p) only if she has time (q )" is equivalent to "If Mariam writes (p), then she has time (q)." Your answer is another form of that: "Mariam only writes if she has time" can move its adjectival "only" to become, "Mariam writes (p) only if she has time (q )."
3. Jonathan says, "I will pass the course only if I get 70% or better on the final exam." Jonathan received 75% on the final exam. Did he pass the course?
You answered:
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Yes.
"I will pass the course only if I get 70% or better on the final exam" is equivalent to "If I pass the course, then I got 70% or better on the final exam." So the argument is:
If I pass then I got 70%+ | --or-- | If P then Q |
Since the argument is invalid, no conclusion can be drawn.
3. Jonathan says, "I will pass the course only if I get 70% or better on the final exam." Jonathan received 75% on the final exam. Did he pass the course?
You answered:
-
No.
"I will pass the course only if I get 70% or better on the final exam" is equivalent to "If I pass the course, then I got 70% or better on the final exam." So the argument is:
If I pass then I got 70%+ | --or-- | If P then Q |