This is a B.pham statistic question..Please help me to solve this

Please don't post with NO work shown.

Really big hint:
1 minus the probability that it will not be solved.

Go!
 
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I did this in many ways..but I can't understand if the events are independent or dependent..
If they are independent the answer will be P(ABC)=P(A)*P(B)*P(C) =43/30
and if It's dependent then the answer will be P(AUBUC)=197/225
Plesse help me to understand which of the process is right and are the events independent or dependent?
 
What does "probability the problem will be solved? Do you mean "solved by at least one person"?
 
P(ABC)=P(A)*P(B)*P(C) =43/30>1. Does that help you?
How did you get 43/30 anyways?
I always thought that a probability is always between 0 and 1 inclusive and if you multiplied three such numbers as in P(A)*P(B)*P(C) your result will also be between 0 and 1 inclusive.
 
How can we decide if the three students responses are independent or not? If the weakest students gets the correct answer then it is probably true that the other two students got the question correct. If the strongest student did not get the correct answer then probably the weakest student would not have gotten the problem correct. But what if the students were equally strong?
 
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I did this in many ways..but I can't understand if the events are independent or dependent..
If they are independent the answer will be P(ABC)=P(A)*P(B)*P(C) =43/30
and if It's dependent then the answer will be P(AUBUC)=197/225
Plesse help me to understand which of the process is right and are the events independent or dependent?
As you were told by tkhunny, you can do this using the complement (subtracting from 1). But first you have to be clear on what the problem means, as it is written in rather poor English.

Assuming it means "What is the probability that at least one person will solve it?", what you want is not P(ABC) (the probability that all three solve it), but 1 - P(not A and not B and not C). Do you see why?

The three events are independent as long as they work separately. That is not a problem. But if they are dependent, you simply don't have enough information; that wouldn't change the problem from an intersection to a union.

But we really need to see the details of your work, as clearly you either did the wrong calculations, or did those calculations wrong. The more details you show, the more quickly you will get useful help.
 
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