16 flat screen tvs. 12 color, 4 b/w. prob. of picking at

Question

16 flat screen tvs.
12 color, 4 b/w.

prob. of picking at least one b/w?

nocilis · Answer

Problem is missing some information - How many times are you picking?

speedo · Answer

Total ways= 2^16 -1= 65535

ways of picking No b/w(ie. All color)= 2^12 -1= 4095

Hence, ways of Atleast one b/w= 65535-4095= 61440

=> P= 61440/65535  ~  0.94

gmatie · Answer

1/8 is the ans.
POSt the OA pls

speedo · Answer

<img src="{SMILIES_PATH}/icon_exclaim.gif" alt=":!:" title="Exclamation" />

HongHu · Answer

This question is very unclear.

speedo · Answer

I don't understand, what is it that you people are not able to understand :?:

There are 12 color TV & 4 b/w TV, 16 in Total. You have to make random selections( pick ). Tell the probability that At Least one b/w TV is there in the selection!! How clear do you want it to be, want the answer hidden somewhere in the Q itself!! :twisted:

You have to make random selections, How can you do that?????????? How many selections?????????? Is that the big :?:

in your minds?? Take three objects(A, B & C), No of selections that can be done: XXX A B C AB AC BC ABC 8 in Total, ie 2^3 Similarly, for 4 objects, it's 2^4= 16 in Total... Do I need to write them as well!! hENCE, FOR 16 TVs/objects, (2^16 -1) different selections possible. (XXX-- None selected case not possible, as atleast one to be selected.) Hence, Total= 2^16 -1= 65535 Similarly, cases where No b/w selected= All colored selected= 2^12 -1= 4095 Subtract from Total & you have the required number!!!! A Very common tendency, if nothing striking in your mind, to say that the Q was not clear, or rather Out of Course!!! :twisted:

HongHu · Answer

What selection? Are we suppose to select one, or two, or 16 TVs? That's where it is unclear. If it meant that a random number of TVs is to be selected, then your solution seems right.

speedo · Answer

Could guess your Qs, alreadt stated them. :twisted:

When Number of selections to be made Not given , by default you are entitled to make Any & every number of selections possible. ie. None, one, two.... n Or in plain math expression: 2^n (including None case)

HongHu · Answer

Exactly. <img src="{SMILIES_PATH}/icon_smile.gif" alt=":)" title="Smile" />

speedo · Answer

:-D we don't need the OA now.

(was waiting, just in case.. but a 3rd party check also equally fine.) :done

16 flat screen tvs. 12 color, 4 b/w. prob. of picking at

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