math problem: compound probability

[balmytigeress 0]

I'm working thru a math textbook, yes I am weird.

My brain is not good at mathmatical gymnastics. I'm stuck on a problem. I have the answers, but it's not helping. It's not a class, so there is no teacher to answer. The examples did not work thru a problem like this one. This is the last section in the chapter and I am anxious to move on.

There is a group of 20 students, 3 are randomly chosen to be on a panel about recent events, here is the distribution of students.

| Freshmen | Sophmore

----------------------------------------------

Male | 4 | 7

-----------------------------------------------

Female | 3 | 6

What is the probability that the panel will consist of:

a) all freshmen

B) all sophmore

c) all females

d) all males

If someone could work thru at least one of these, it would be a big help.

Please!

Thanks!

[one...two...tree 2,762]

I'm working thru a math textbook, yes I am weird.

My brain is not good at mathmatical gymnastics. I'm stuck on a problem. I have the answers, but it's not helping. It's not a class, so there is no teacher to answer. The examples did not work thru a problem like this one. This is the last section in the chapter and I am anxious to move on.

There is a group of 20 students, 3 are randomly chosen to be on a panel about recent events, here is the distribution of students.

| Freshmen | Sophmore

----------------------------------------------

Male | 4 | 7

-----------------------------------------------

Female | 3 | 6

What is the probability that the panel will consist of:

a) all freshmen

B) all sophmore

c) all females

d) all males

If someone could work thru at least one of these, it would be a big help.

Please!

Thanks!

There are a total Male population of 11, so...

Male Population Ratio = 11/20 or 55 % of the population

Female Population Ration = 9/20 or 45 % of the population

a) panel = 3/20 so multiply that ratio by the freshman population ratio ...3/20 X 7/20

Hopefull you can follow how to set the rest of the equations up.

[rika60607 215]

Here you go:

I calculate the probability of all females ©:

Females are 9/20. If panel was 1 person, chances of all female would be 9/20. If two person panel 9/20 multiply by 8/19 (second probability is influenced by first probability here). Three person panel multiply 9/20 by 8/19 by 7/18.

Let us know correct answer!!!

Rika

I'm working thru a math textbook, yes I am weird.

My brain is not good at mathmatical gymnastics. I'm stuck on a problem. I have the answers, but it's not helping. It's not a class, so there is no teacher to answer. The examples did not work thru a problem like this one. This is the last section in the chapter and I am anxious to move on.

There is a group of 20 students, 3 are randomly chosen to be on a panel about recent events, here is the distribution of students.

| Freshmen | Sophmore

----------------------------------------------

Male | 4 | 7

-----------------------------------------------

Female | 3 | 6

What is the probability that the panel will consist of:

a) all freshmen

B) all sophmore

c) all females

d) all males

If someone could work thru at least one of these, it would be a big help.

Please!

Thanks!

[rika60607 215]

So what's the answer??????

[balmytigeress 0]

Rika - you were right. Yesterday I was putting the numbers correctly, but my math was coming out wrong or I wasn't simplifying my fractions correctly, so I wasn't coming up with the right answer and I go really confused and of course using the other methods in the section did not work. I did that alot in math classes, mix up the numbers - write them down wrong or do the basic math wrong, so most of my answers were wrong and I got bad grades. So I hated math class and didn't put as much effort in because I was really trying but it didn't do any good. Now here I am, checking out a math book from the library because math skills are good to have for work and I lack the feeling that I would be good for ANY job, so I guess it is a self-confidence thing. Building up on basics.

Yaaaay! Now I can finish this chapter and move on to finish chapter 5 - which I skipped to when I ran into this problem I thought I had with chapter 4. Chapter 6 seems fun, mathematical systems, which is modular systems like 12 hour clock. I was thinking about taking an actual classroom class, but I like being able to breeze thru what I know already and take extra time on the rest. In a math class there is no way I would have been able to go thru 5 chapters in 2 weeks.

Well, thank you!

The answers are

a: 7 / 228

b: 143 / 570

c: 7 / 95

d: 11 / 76

Edited August 12, 2007 by balmytigeress

[rika60607 215]

Yay, I am good for something :dance:

I wish I had time to do what you are doing. But always something destructs me!

Good luck

Rika

Rika - you were right.

Yaaaay! Now I can finish this chapter and move on to finish chapter 5 - which I skipped to when I ran into this problem I thought I had with chapter 4. Chapter 6 seems fun, mathematical systems, which is modular systems like 12 hour clock. I was thinking about taking an actual classroom class, but I like being able to breeze thru what I know already and take extra time on the rest. In a math class there is no way I would have been able to go thru 5 chapters in 2 weeks.

Well, thank you!

The answers are

a: 7 / 228

b: 143 / 570

c: 7 / 95

d: 11 / 76

[Jasman0717 9]

[Clarky and Tarah 0]

Exactly how I feel. Math gives me a headache