Jose is paying for a meal using bills in his wallet. He has five $1 bills and four $5 bills. If he selects two bills at random, one at a time from his wallet, without replacement, what is the probability that he will choose two $5 bills to pay for the meal?

Question

Jose is paying for a  meal using bills in his wallet. He has five $1  bills and four $5  bills. If he selects two bills at random, one at a time from his wallet, without replacement, what is the probability that he will choose two  $5 bills to pay for the meal?

ganpat · Answer

2/4 =  1/2...

ganpat · Answer

@mathslover : dude is this right ?? m lil confused..

ledah · Answer

I'm assuming since this is probability there's a 4 out of 9 chance it will be two 5$ bills.

ledah · Answer

there's also a 5 out of 9 it will be a $1 bill

ganpat · Answer

or 2/ 4 * 4/9 = 2/ 9 ??  How abt this ??

ledah · Answer

well I don't quite think that would be correct. because there are more than 2 $5 bills

ganpat · Answer

hmmm.. @ganeshie8 ??

anonymous · Answer

thanks a lo
t ganpat

ganpat · Answer

dude wait.. m not sure on this..

ledah · Answer

I'm going to assume my attempt to help was ignored.

anonymous · Answer

i think it's near of the answer 0.6 * 0.6

anonymous · Answer

it wasnt

ledah · Answer

This has nothing to do with multiplication....

anonymous · Answer

divide the problem into two steps. 
step 1: probability of getting $5 bill out off 9 bills, of which 4 are of its own kind (i.e. $5)
probability for that would be 4/9
step 2: probability of getting $5 bill out off 8 bills, of which 3 are of its own kind (i.e. $5)
probability for that would be 3/8
now multiply these two figures for answer. it would be 1/6

ganpat · Answer

@Ledah : ha ha, dont get angry dude.. just trying to make it more clear...

ledah · Answer

I'm not angry I'm just speaking my mind.

ganpat · Answer

@vamgadu : 3/ 8 ?? were did this come from ?

ledah · Answer

Yeah... where did that come from?

anonymous · Answer

when you have removed one $5 bill successfully, there would only be 8 bills in there. as u have removed a $5 bill out the four, there will only be 3 left. so the probability of getting a $5 bill is 3/8

ledah · Answer

..... I don't think it means removed.... ermm... I believe that it should be  what I said earlier.

ganpat · Answer

@vamgadu : yes.. it says one at a time..

ledah · Answer

Confused me.

anonymous · Answer

okay that's mean multy by 2

anonymous · Answer

me to do not know what to put as an answer

anonymous · Answer

for at once time two bills

ledah · Answer

And now I'm completely... confused. Awesome! -_-

anonymous · Answer

ahhhhhhhhhhhhhhhhhhhhhhhhhhhh

anonymous · Answer

the question said the bills are taken out one at a time without replacement. so It is presumed that they are removed

anonymous · Answer

yes

ledah · Answer

But this is still probability.

anonymous · Answer

yeah

ledah · Answer

so you wouldn't remove the numbers just because it says removed.

anonymous · Answer

you do have to or it will be wrong

ganpat · Answer

@vamgadu : so that is right..  4/ 9 * 3/8... 1/6..

i agreee

ledah · Answer

hmm. very well then.

anonymous · Answer

so is it %
17

ganpat · Answer

yes.. 17%

anonymous · Answer

??

ganpat · Answer

1/ 6 = 0.1666 = 0.17 = 17 %