noviceprobability
New member
- Joined
- Nov 2, 2016
- Messages
- 1
Hello , sorry I have a quiz coming soon and I am rushing to understand these questions but I cannot understand. I hope someone can help me in these! Its a long list for several questions but the answers are provided.. I need the workings and explanations though. I am afraid of failing my quiz.
Question 3
Find the number of different signals that can be generated by arranging exactly 2 flags in order (one below the other) on a vertical staff, if five different flags are available.
The answer provided was '' The order of the flags determines the meaning of the signal so in this case we calculate the number of permutations of 2 to 5 .
So what is the numerical answer for this question? I do not understand because is this question supposed to be repetition of flags allowed or no repetition?
Question 6
0 out of 10 points
In a random sample of 100 students 60 list music as one of their hobbies, 40 list sport as a hobby and 85 list socialising as a hobby. Assume the events are statistically independent. Use Venn diagrams to calculate the following:
a) The likelihood that a student lists music as a hobby
Correct Answer:
Correct 0.6
Answer range +/-
0 (0.6 - 0.6)
Response Feedback:
Let M be the event that a student likes Music, Let Sp be the event that a student likes Sport, Let Sc be the event that a student likes Socialising
P(M) = 0.6 is an example of simple probability
Is the working 60 divided by 100 to give you 0.6?
Question 7
In a random sample of 100 students 60 list music as one of their hobbies, 40 list sport as a hobby and 85 list socialising as a hobby. Assume the events are statistically independent. Use Venn diagrams to calculate the following:
b) The probability that a student participates in music, sport and socialising,
Correct Answer:
Correct 0.204
Answer range +/-
0 (0.204 - 0.204)
Response Feedback:
Let M be the event that a student likes Music, Let Sp be the event that a student likes Sport, Let Sc be the event that a student likes Socialising
The events are independent so P(M and Sp and Sc) = 0.205 is an example of joint probability calculated using the multiplication rule
I do not know how to get answer 0.205 because there is no workings.
Question 8
In a random sample of 100 students 60 list music as one of their hobbies, 40 list sport as a hobby and 85 list socialising as a hobby. Assume the events are statistically independent. Use Venn diagrams to calculate the following:
c) The probability that a student lists music or sport as a hobby.
Correct Answer:
Correct 0.76
Answer range +/-
0 (0.76 - 0.76)
Response Feedback:
Use the general addition rule
What is the maths working for this? I do not know because there is no workings provided , only answers and I do not know how to find the answers.
Question 9
0 out of 10 points
At a certain university function, 6% of the participants are commerce students, event C. 50% of all participants are female, event F while 3% of participants are females and commerce students. Suppose a participant is selected at random. Use a contingency table to help find the following probabilities and interpret the result:
a) P(C | F);
Correct Answer:
Correct 0.06
Answer range +/-
0 (0.06 - 0.06)
Is P(C | F) = P(C&F) divided by P(F) ? Or is P(C | F) = P(C) divided by P(F)? I am getting confused.
Question 10
0 out of 10 points
At a certain university function, 6% of the participants are commerce students, event C. 50% of all participants are female, event F while 3% of participants are females and commerce students. Suppose a participant is selected at random. Use a contingency table to help find the following probabilities and interpret the result:
b) P(C and F);
Correct Answer:
Correct 0.03
Answer range +/-
0 (0.03 - 0.03)
Likewise , it seems the questions are interrelated so I can't do the rest without solving the previous questions I guess. And I am confused by P(C&F). Is P(C&F) = P(C) divided by P(F)? or is P(C&F) equals P(C)+P(F)?
Question 11
0 out of 10 points
At a certain university function, 6% of the participants are commerce students, event C. 50% of all participants are female, event F while 3% of participants are females and commerce students. Suppose a participant is selected at random. Use a contingency table to help find the following probabilities and interpret the result:
c) P(F | C);
Correct Answer:
Correct 0.5
Answer range +/-
0 (0.5 - 0.5)
Workings needed.
Question 12
0 out of 10 points
At a certain university function, 6% of the participants are commerce students, event C. 50% of all participants are female, event F while 3% of participants are females and commerce students. Suppose a participant is selected at random. Use a contingency table to help find the following probabilities and interpret the result:
d) P(C and M), where M is the event that a student is male;
Correct Answer:
Correct 0.03
Answer range +/-
0 (0.03 - 0.03)
i tried P(C) divided by P(M) and it was 0.03 divided by 0.5 and it gave me a different answer to the correct answer. I am lost .
Question 3
Find the number of different signals that can be generated by arranging exactly 2 flags in order (one below the other) on a vertical staff, if five different flags are available.
The answer provided was '' The order of the flags determines the meaning of the signal so in this case we calculate the number of permutations of 2 to 5 .
So what is the numerical answer for this question? I do not understand because is this question supposed to be repetition of flags allowed or no repetition?
Question 6
0 out of 10 points
In a random sample of 100 students 60 list music as one of their hobbies, 40 list sport as a hobby and 85 list socialising as a hobby. Assume the events are statistically independent. Use Venn diagrams to calculate the following:
a) The likelihood that a student lists music as a hobby
Correct Answer:
Correct 0.6
Answer range +/-
0 (0.6 - 0.6)
Response Feedback:
Let M be the event that a student likes Music, Let Sp be the event that a student likes Sport, Let Sc be the event that a student likes Socialising
P(M) = 0.6 is an example of simple probability
Is the working 60 divided by 100 to give you 0.6?
Question 7
In a random sample of 100 students 60 list music as one of their hobbies, 40 list sport as a hobby and 85 list socialising as a hobby. Assume the events are statistically independent. Use Venn diagrams to calculate the following:
b) The probability that a student participates in music, sport and socialising,
Correct Answer:
Correct 0.204
Answer range +/-
0 (0.204 - 0.204)
Response Feedback:
Let M be the event that a student likes Music, Let Sp be the event that a student likes Sport, Let Sc be the event that a student likes Socialising
The events are independent so P(M and Sp and Sc) = 0.205 is an example of joint probability calculated using the multiplication rule
I do not know how to get answer 0.205 because there is no workings.
Question 8
In a random sample of 100 students 60 list music as one of their hobbies, 40 list sport as a hobby and 85 list socialising as a hobby. Assume the events are statistically independent. Use Venn diagrams to calculate the following:
c) The probability that a student lists music or sport as a hobby.
Correct Answer:
Correct 0.76
Answer range +/-
0 (0.76 - 0.76)
Response Feedback:
Use the general addition rule
What is the maths working for this? I do not know because there is no workings provided , only answers and I do not know how to find the answers.
Question 9
0 out of 10 points
At a certain university function, 6% of the participants are commerce students, event C. 50% of all participants are female, event F while 3% of participants are females and commerce students. Suppose a participant is selected at random. Use a contingency table to help find the following probabilities and interpret the result:
a) P(C | F);
Correct Answer:
Correct 0.06
Answer range +/-
0 (0.06 - 0.06)
Is P(C | F) = P(C&F) divided by P(F) ? Or is P(C | F) = P(C) divided by P(F)? I am getting confused.
Question 10
0 out of 10 points
At a certain university function, 6% of the participants are commerce students, event C. 50% of all participants are female, event F while 3% of participants are females and commerce students. Suppose a participant is selected at random. Use a contingency table to help find the following probabilities and interpret the result:
b) P(C and F);
Correct Answer:
Correct 0.03
Answer range +/-
0 (0.03 - 0.03)
Likewise , it seems the questions are interrelated so I can't do the rest without solving the previous questions I guess. And I am confused by P(C&F). Is P(C&F) = P(C) divided by P(F)? or is P(C&F) equals P(C)+P(F)?
Question 11
0 out of 10 points
At a certain university function, 6% of the participants are commerce students, event C. 50% of all participants are female, event F while 3% of participants are females and commerce students. Suppose a participant is selected at random. Use a contingency table to help find the following probabilities and interpret the result:
c) P(F | C);
Correct Answer:
Correct 0.5
Answer range +/-
0 (0.5 - 0.5)
Workings needed.
Question 12
0 out of 10 points
At a certain university function, 6% of the participants are commerce students, event C. 50% of all participants are female, event F while 3% of participants are females and commerce students. Suppose a participant is selected at random. Use a contingency table to help find the following probabilities and interpret the result:
d) P(C and M), where M is the event that a student is male;
Correct Answer:
Correct 0.03
Answer range +/-
0 (0.03 - 0.03)
i tried P(C) divided by P(M) and it was 0.03 divided by 0.5 and it gave me a different answer to the correct answer. I am lost .