Please help me.. if I can at least get a start that would be great

3. Find the probability of getting 2 hearts if the cards are drawn from a regular deck and the first card is not replaced.

4. A true/false quiz consists of twenty questions. If a student answers the twenty questions by making random guesses, what is the probability of getting at least one correct answer?


6. Using the accompanying probability distribution, find the following values
X P(x)
1 .25
2 .27
3 .05
4 .43

a) Mean
b) Standard Deviation


7. A contest entrant has a .00001 probability of winning $5,000.00. If this is only prize and the entry fee is $20.00, then what is the expected value?


8. Assume that the cure rate for a certain drug is 20% and that 15 patients are tested with this drug. Find the following:
a) Mean
b) Standard Deviation
c) P (exactly 4 cures)
d) P (exactly 4 cures)


10. A snack company distributes chips in bags labeled 6 ounces. The local Bureau of Weights and Measures randomly selects 50 bags of chips and obtains a sample mean of 5.9 ounces. Assuming that the standard deviation is known to be 0.8, test the claim at the .05 significance level that the bags contain less than 6 ounces. Identify the following:

a) The Null Hypothesis
b) Critical Value
c) Test Statistics
d) Your Conclusion regarding the Null Hypothesis
e) Your Statement regarding the claim.