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suhana

Member

Registered: 2011-02-25

Posts: 31

how to solve this problem? any one can teach me right...

an international audit company located in malaysia. the company, found that 63% of auditorsare Malaysia and the balance is a nan-malaysians.mong Malaysia, 47% were graduates of international flash, 26% are local fresh graduates and the rest internationally experienced and trained auditos. otherwise, between the non-Malaysia, 33% were international graduates fresh, 18% are local fresh graduates and the rest are international auditors are experienced and trained.

a) for a description of the above, construct a tree diagram.

b) determining the probability that the auditor randomly selected by an experienced international.

c) What is the probability that a randomly selected auditor is a local graduate frash.

d) given that the auditor is a fresh international graduates, find the probability that the auditor is a Malaysian

Bob

Administrator

Registered: 2010-06-20

Posts: 10,583

Re: how to solve this problem? any one can teach me right...

hi suhana,

(a) I've put a tree diagram below.

The two branches at the start must add to probability = 1.00 and similarly the three branches for the type of auditor must add to 1.00 so I have worked out the missing probabilities.

Then you can calculate the six outcomes by multiplying the probabilities on the branches.  I have started the calculation for Malaysians who are experienced to show what I mean.

When you have calculated all six, check that these answers add up to 1 as well and search for errors if they don't!

(b)  you can then add up two answers for this.

(c)  Similarly here.

(d)  let x = P(fresh international graduate) and y = (Malaysian and fresh international graduate) then the answer here is y ÷ x

Hope that tells you all you need to finish the problem.  If not, post again.

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

suhana

Member

Registered: 2011-02-25

Posts: 31

Re: how to solve this problem? any one can teach me right...

thank you very

may I ask,
how do you have this answers
can you explain please..

p (non-m) = 0:37?
p (exp) = 0:27?
p (exp) = 0.49?

Bob

Administrator

Registered: 2010-06-20

Posts: 10,583

Re: how to solve this problem? any one can teach me right...

hi suhara,

An auditor is a Malayian or is not a Malayian

so P(Malay) + P(Not M) = 1 ..................................  (one of these two must happen)

So P(NotM) = 1 - 0.63 = 0.37

In the same way a Malayian auditor must be international, local or experienced,  so

P(inter) + P(local) + P(exp) = 1

P(exp) = 1 - 0.47 - 0.26 = 0.27

and for not Malayians

P(exp) = 1 - 0.33 - 0.18 = 0.49

OK ?

Bob

Last edited by Bob (2011-02-26 02:01:38)

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

suhana

Member

Registered: 2011-02-25

Posts: 31

Re: how to solve this problem? any one can teach me right...

ok done, i understand answer (a)..tq:)

how about (b)

you tell me --> "you can then add up two answers for this"

did you mean about this?

international experienced?
p(exp)=0.27
p(exp)=0.49
0.27+0.49
=0.76

it's true or not?or another solution?..

Bob

Administrator

Registered: 2010-06-20

Posts: 10,583

Re: how to solve this problem? any one can teach me right...

hi suhana

(b)  see diagram below

I have put in some more probabilities.  (highlights in purple)

You need to do 4 more calculations like these.

P(M and e)          = 0.1701
P(not M and exp) = 0.1813

To get all the experienced auditors you must add these 2 answers

P(exp) = 0.1701 + 0.1813 = .........

I am making a new post which should help you to understand this method.

Bob

Last edited by Bob (2011-02-26 03:32:56)

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

Bob

Administrator

Registered: 2010-06-20

Posts: 10,583

Re: how to solve this problem? any one can teach me right...

hi suhana,

This may help you to understand the "Tree Diagram" method.

Imagine there are exactly 10000 auditors.  63% are Malaysians .......

The diagram below shows how they are divided according to the %.

To get the probability of an experienced auditor add up 1701 and 1813 = 3514.

Now divide by 10000.

P(exp) = 0.3514

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

suhana

Member

Registered: 2011-02-25

Posts: 31

Re: how to solve this problem? any one can teach me right...

a)
P(NotM) = 1 - 0.63 = 0.37 <--P(non-M)
P(inter) + P(local) + P(exp) = 1
P(exp) = 1 - 0.47 - 0.26 = 0.27<--P(Exp)<--answer for (m)
P(exp) = 1 - 0.33 - 0.18 = 0.49<--P(Exp)<--answer for (non-m)

b)

P(M and exp)          = 0.1701
P(not M and exp)     = 0.1813
P(exp) = 0.1701 + 0.1813 = 0.3514<--answer for probability that a randomly (inter exp)

it' true completion of path the work?

and  (C)  Similarly here ?do you main?

p/s :SORRY BOB I ASK TO MANY BECOUSE I NOT UNDERSTAND MY LECTURER EXPLAIN BECAUSE SHE GIVE MORE AND ANSWER AND I DO KNOW WHERE ANSWER FOR QUESTION A,B,C,OR ANY QUESTION...

suhana

Member

Registered: 2011-02-25

Posts: 31

Re: how to solve this problem? any one can teach me right...

yes!! i have answer...and understand..

(c)(C)  Similarly here ?do you main similarly at Q(b)

P(M and local)          = 0.1638
P(not M and local)     = 0.0666
P(local) = 0.1638+ 0.0666 = 0.2304<--answer for probability that a randomly (inter fresh)

it's true or not?

suhana

Member

Registered: 2011-02-25

Posts: 31

Re: how to solve this problem? any one can teach me right...

(d)
let x = P(fresh international graduate) and y = (Malaysian and fresh international graduate) then the answer here is y ÷ x

you main...

x=p(fresh international graduate)
y=(Malaysian and fresh international graduate)0.63x0.47

x=0.47x0.33
  =0.1551
y=0.63x0.47
  =0.2961

y ÷ x
=0.1551  ÷ 0.2961
=0.5238

it's true or not?

Bob

Administrator

Registered: 2010-06-20

Posts: 10,583

Re: how to solve this problem? any one can teach me right...

hi suhana,

  You are getting there.  a, b and c   all correct! 

But not d. 

d) given that the auditor is a fresh international graduates

so you must only look at those auditors

x = 0.2961 + 0.1221 = 0.4182

y is correct

then d = Malaysian internetaionals ÷ all internationals
          = y ÷ x
          = 0.2961 ÷ 0.4182
          = 0.708034

Hope that helps,

I can find another question like this if you want to try it.  Just post back if you do.

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

suhana

Member

Registered: 2011-02-25

Posts: 31

Re: how to solve this problem? any one can teach me right...

haii bob,

touched because you're willing to help me...

bob... can you help the next question which I attach yesterday...
please...been my best and I do not sleeping from the yesterday .. not me do not finding but I have tried to do my own ;(