dbt in the question

A bag contains 8 red and 5 white balls.Three balls are drawn at random.Find the Probability that

All the three balls are white

in solving this question i have a doubt can we take 5 white balls as identical or not.can u explain for ur reasons

64 Answers

3
msp ·

pls post ur solns.
i still not clear abt the option a can u explain abt the option a

3
msp ·

praji soln needed da.

1
MATRIX ·

itz 5C3 sankara!!!!!!!!

39
Dr.House ·

its a simple application of baye`s theorem na

3
msp ·

wait i will give u the other part of the question

A bag contains 8 red and 5 white balls.Three balls are drawn at random.Find the Probability that
II)One ball is red and two balls are white

1
MATRIX ·

1) E: Probability of getting 3 balls are white ......

P(E) = (8C0 X 5C3)/ 13C3

= 1 X 5 X 4 X 3/13 X12 x 11

= 5/143

2) E: Probability of getting one red ball and 2 white balls

P(E) = (8C1 X 5C2)/ 13C3

= 8 X 5 X 4/ 13 X 12 X 11 X 2

= 20/429

Got it Sankara!!!!!!!!!

3
msp ·

wait y do u take the 5 white and 8 red balls r distinct [7]

39
Dr.House ·

ok yaar, again its baye`s theorem na!!!!!! {correct me if i am wrong}

3
msp ·

wat prajith is done is rite da.

39
Dr.House ·

sankara it is not needed wether same or different. tell me what makes the difference

3
msp ·

can u explain y bayes theorem applies here

3
msp ·

if it is distinct then u can select 3 balls out of 5 balls in 5C3

39
Dr.House ·

sankara dont feel bad, but u say which other method works here? i dont see anyway any other thing works.

although some may work but i dont think u know that as it is not in jee syllabus.

3
msp ·

if they are identical object

take an example consider 5 identical photos Mr.Ramanujan sir then wat is the no of way to take 3 identical photos from the 5 identical photos

1
MATRIX ·

Sanakar i have given the answer for the 2 questions of urs!!!! r u satisfied with it!!!!!!!

3
msp ·

noooooooooooooooooooo

3
msp ·

first ans the 14th post

1
skygirl ·

isme baye's kyun ??

39
Dr.House ·

why do u think wether to take identical or different?

3
msp ·

no da.how it will be 5C3.can u give the proof da.

39
Dr.House ·

answer bolo da.

3
msp ·

i am confused mathe but prajith's soln is rite da

3
msp ·

ans for wat question da

1
skygirl ·

here its not identical....

if it was so, then ways of selecting three balls from 5 would have been one ...

3
msp ·

for the 14th one i think it shud be 1 becos u cant distinguish 5 identical things

39
Dr.House ·

wahii to bal rahan hoon. we have to take them as distinct, if u want to get the answer. we are not specified anything here na.

1
MATRIX ·

Well sankara!!!!!!!
for taking 3 identical photos out of 5 identical ones the probability is 5C3

As ur not taking 5 ones together itz not 5C5

so ur taking 3 identical ones out of 5 identical photos at a time...........so itz probability is 5C3........wats the doubt in that sankara!!!!!!!!!!

3
msp ·

yes one sky but i think lot of pbms were based on this question . wat can i do shall i assume all these type of problems as distinct objects

3
msp ·

yes i didnt get this thought b555 at my exam . i put option d none of these so i was awarded -ive

39
Dr.House ·

u ask me how to use phaltoo tricks in exam, i am a pro in dat.

Your Answer

Close [X]