quiz contains a multiple-choice question with five possible answers, only one of which is correct...

eddy2017

eddy2017

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A quiz contains a multiple-choice question with five possible answers, only one of which is correct. A student plans to guess the answer.
a) What is the sample space?
b) Assign probabilities to the simple events
c) Probability student guesses the wrong answer
d) Probability student guesses the correct answer

hi dear tutors, i need you to confirm is my answers were right.

a) sample space =5 (all the possble outcomes)
b) ? do not understand it.
c) there are five outcomes that might be unfavorable for him so probalility of him guessing the worng anser = 5
d) favorable outcomes=1

do not undertand b, i'll appreciate if you drop a hint my way,
eddy
 
i know this, but still do not understand what the item asks of me to do.
''A simple event results in just one outcome. For instance, if we flip one coin, it will result in just one outcome. The coin could either land on heads, or it could land on tails. A compound event is an event containing more than one outcome''.
 
eddy2017 said:
A quiz contains a multiple-choice question with five possible answers, only one of which is correct. A student plans to guess the answer.
a) What is the sample space?
b) Assign probabilities to the simple events
c) Probability student guesses the wrong answer
d) Probability student guesses the correct answer

hi dear tutors, i need you to confirm is my answers were right.

a) sample space =5 (all the possble outcomes)
b) ? do not understand it.
c) there are five outcomes that might be unfavorable for him so probalility of him guessing the worng anser = 5
d) favorable outcomes=1

do not undertand b, i'll appreciate if you drop a hint my way,
eddy
Click to expand...
I think you need to do some reading (or rereading) on the topic of probability. Probability can't be greater than 1.
 
lev888 said:
I think you need to do some reading (or rereading) on the topic of probability. Probability can't be greater than 1.
Click to expand...
I have studied the subject. Yes, probability moves between 0 and 1.it can not be 0 and and it can't certainly be 1 either .
Probability of getting the wrong answer 1/4
Probababiity of getting the right answer 1/5
 
I forgot that it is always expeessed in fraction form
Assigning probability to a simple event is what gets me.
 
eddy2017 said:
A quiz contains a multiple-choice question with five possible answers, only one of which is correct. A student plans to guess the answer.
a) What is the sample space?
b) Assign probabilities to the simple events
c) Probability student guesses the wrong answer
d) Probability student guesses the correct answer

hi dear tutors, i need you to confirm is my answers were right.

a) sample space =5 (all the possble outcomes)
b) ? do not understand it.
c) there are five outcomes that might be unfavorable for him so probalility of him guessing the worng anser = 5
d) favorable outcomes=1

do not undertand b, i'll appreciate if you drop a hint my way,
eddy
Click to expand...
A student can pick "wrong" answer 4 ways.

A student can pick "correct" answer 1 way.

Now think again.....
 
eddy

You got excellent answers. I am, I hope, supplementing them.

The sample space is the entire list of simple events. That list is picking option 1, 2, 3, 4, or 5. That was question a. You got it right.

If one out of n simple events is picked at random, then the probability of each simple event is 1/n. in this case it is 1/5. The question was not well phrased because it did not include the phrase “at random.” (You may doubt that humans can actually do anything randomly, but that assumption was implicit in question b.)

Now, in your first answer, you said that the probability of the student guessing the wrong answer was FIVE.
When lev said that a probability cannot be greater than 1, you said in response that a probability cannot be zero or one. But that is an error. The probability of an event can be zero. What does that mean? The probability of an event can be one. What does that mean?

And yes, under the assumption of random picking, the probability of a wrong answer is 4/5.
 
JeffM said:
eddy

You got excellent answers. I am, I hope, supplementing them.

The sample space is the entire list of simple events. That list is picking option 1, 2, 3, 4, or 5. That was question a. You got it right.

If one out of n simple events is picked at random, then the probability of each simple event is 1/n. in this case it is 1/5. The question was not well phrased because it did not include the phrase “at random.” (You may doubt that humans can actually do anything randomly, but that assumption was implicit in question b.)

Now, in your first answer, you said that the probability of the student guessing the wrong answer was FIVE.
When lev said that a probability cannot be greater than 1, you said in response that a probability cannot be zero or one. But that is an error. The probability of an event can be zero. What does that mean? The probability of an event can be one. What does that mean?

And yes, under the assumption of random picking, the probability of a wrong answer is 4/5.
Click to expand...
yes, you're right. i was more than vague. i have studied a little bit probability. like lev said, i need to go deeper into it which i plan to do.
the properties of probability that i have studied state that is always gonna be a decimal or fraction between 0 and 1 but it is inclusive of 0 and 1. you are right. it is only that if P=0 then we have an impossible event and if P=1 then we call this event a certain event.
 
i understand, maybe wrongly, that if an event has zero probability of happening then that means that the event is impossible. it will never come to pass.
i still do not understand this here even when i have a superficial knowledge of the three approaches to assigning probability:
the classical , the relative frequency approach, and the subjective approach.
b) Assign probabilities to the simple events ??
 
JeffM said:
eddy

You got excellent answers. I am, I hope, supplementing them.

The sample space is the entire list of simple events. That list is picking option 1, 2, 3, 4, or 5. That was question a. You got it right.

If one out of n simple events is picked at random, then the probability of each simple event is 1/n. in this case it is 1/5. The question was not well phrased because it did not include the phrase “at random.” (You may doubt that humans can actually do anything randomly, but that assumption was implicit in question b.)

Now, in your first answer, you said that the probability of the student guessing the wrong answer was FIVE.
When lev said that a probability cannot be greater than 1, you said in response that a probability cannot be zero or one. But that is an error. The probability of an event can be zero. What does that mean? The probability of an event can be one. What does that mean?

And yes, under the assumption of random picking, the probability of a wrong answer is 4/5.
Click to expand...
You may doubt that humans can actually do anything random....yes, they can. a lot! lol.
thanks for the comment. very helpful.
 
eddy2017 said:
i understand, maybe wrongly, that if an event has zero probability of happening then that means that the event is impossible. it will never come to pass. ( that is, if zero probability and impossibility mean the same, which i do not really know)

i still do not understand this here even when i have a superficial knowledge of the three approaches to assigning probability:
the classical , the relative frequency approach, and the subjective approach.
b) Assign probabilities to the simple events ??
Click to expand...
 
I have to tell you that I suspect reading about the different conceptual understandings of the epistemological status of probability theory is not likely to help with the mathematical application of probability theory.

As I said before, the question was badly posed. It is unanswerable on the information given. However, if the guessing student has a true randomizing device and assigns equal weights to the possible answers, the probability of choosing any answer is 1/5. You are supposed to assume that the events have equal probabilities.
 
JeffM said:
I have to tell you that I suspect reading about the different conceptual understandings of the epistemological status of probability theory is not likely to help with the mathematical application of probability theory.

As I said before, the question was badly posed. It is unanswerable on the information given. However, if the guessing student has a true randomizing device and assigns equal weights to the possible answers, the probability of choosing any answer is 1/5. You are supposed to assume that the events have equal probabilities.
Click to expand...
ok, thanks. and what is item b)?. still no answer or clue>
 
JeffM said:
I just told you. The answer they expect is 1/5. It is a dumb question.
Click to expand...
okay, Jeff, thanks a lot. i got confused after reading about the different ways of assigning probailities. i was in doubt if they were asking about that.
 
eddy2017 said:
A quiz contains a multiple-choice question with five possible answers, only one of which is correct. A student plans to guess the answer.
a) What is the sample space?
b) Assign probabilities to the simple events
c) Probability student guesses the wrong answer
d) Probability student guesses the correct answer

hi dear tutors, i need you to confirm is my answers were right.

a) sample space =5 (all the possble outcomes)
b) ? do not understand it.
c) there are five outcomes that might be unfavorable for him so probalility of him guessing the worng anser = 5
d) favorable outcomes=1

do not undertand b, i'll appreciate if you drop a hint my way,
eddy
Click to expand...
The size of the sample space may be 5 but the same space is NOT 5. So what is the sample space?
 
Jomo said:
The size of the sample space may be 5 but the sample space is NOT 5. So what is the sample space?
Click to expand...
You got me there. As i understand it,the size of the sample space is the total number of possible outcomes. Not favorable but possible. And there are 5 possible answers. So i do not undertand your question.
 
The event space is the number of outcomes in the event you are interested in. According to this definition, the sample space is 1.
The event space of getting 1 question correct out of 4.
The size of the sample space is the total number of possible outcomes.
Yes, they are not the same. I am not sure if i grasped the dif well.
If it is not that, then i don't know thexanswer to your question.
 
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eddy2017 said:
You got me there. As i understand it,the size of the sample space is the total number of possible outcomes. Not favorable but possible. And there are 5 possible answers. So i do not undertand your question.
Click to expand...
The sample space is all the possible outcomes, and the event space is the outcomes in the event.
Can you give me this exercise as an example, if i am wrong, and please explain if you will, how you get to tell one from the other?.
 
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