# Math Help - Discrete Probability Distribution

1. ## Discrete Probability Distribution

Q3: 0.7383
Q6: 0.6472, (i)2.328, (ii)0.8171
Q7: (i)0.223, (ii)0.934, (iii)0.050

2. Originally Posted by cloud5

Q3: 0.7383
Q6: 0.6472, (i)2.328, (ii)0.8171
Q7: (i)0.223, (ii)0.934, (iii)0.050
I will do 3 first, will be back for (6) and (7) after dinner if no other posters have replied.

For (3), since the puzzle on Monday has been solved, he is only left with 4 puzzles to solve. This is a case of a binomial distribution.

X~B(4 , 3/4)

Then calculate P(X>=3)

3. #6

Set up a probability distribution table, with Y=0,1,2,3,>3. Calculate their respective probabilities. Then E(x) and Var(x) will follow.

Next, find the mode of the distribution. This is similar to the question asked in your previous post.

#7

X~P(3)

Calculate P(X=0)

4. Originally Posted by mathaddict
Then calculate P(X>=3)
How did you know is P(X>=3)? When I first do this, I used P(X>=4), no wonder I can't get the answer. ^^''

5. Originally Posted by cloud5
How did you know is P(X>=3)? When I first do this, I used P(X>=4), no wonder I can't get the answer. ^^''
Because he has already solved one of the 5 puzzles (the one on Monday) so there are 4 puzzles left to be solved in that week.