1.A researcher wants to evaluate whether countries with lower fertility rates have a higher life expectancy. They collect the fertility rates and the life expectancies of countries around the world. Is this an observation or an experiment? Why?

2.A statistics class has the following activities and weights for determining a grade in the course: test 1 worth 15% of the grade, test 2 worth 15% of the grade, test 3 worth 15% of the grade, homework worth 10% of the grade, semester project worth 20% of the grade, and the final exam worth 25% of the grade. If a student receives an 85 on test 1, a 76 on test 2, an 83 on test 3, a 74 on the homework, a 65 on the project, and a 79 on the final, what grade did the student earn in the course?

3.Suppose you take a standardized test and you are in the 10th percentile. What does this percentile mean? Can you say that you failed the test? Explain.

4.You are going to a benefit dinner, and need to decide before the dinner what you want for salad, main dish, and dessert. You have 2 different salads to choose from, 3 main dishes, and 5 desserts. How many different meals are available?

5.You have a group of twelve people. You need to pick a president, treasurer, and secretary from the twelve. How many different ways can you do this?

6.An urn contains five red balls, seven yellow balls, and eight white balls. How many different ways can you pick two red balls?

7.How many ways can you choose seven people from a group of twenty?

8.The commuter trains on the red Line for the Regional Transit

Authority (RTA) have a waiting time during peak rush hour periods of ten minutes

a.) State the random variable.

b.) Find the probability of waiting between two and five minutes.

c.) Find the probability of waiting between seven and ten minutes.

d.) Find the probability of waiting eight minutes exactly

9.A study conducted found the length of Atlantic cod to have a mean

of 49.9 cm and a standard deviation of 3.74 cm. Assume the length of fish is normally distributed.

a.) State the random variable.

b.) Find the probability that an Atlantic cod has a length less than 52 cm.

c.) Find the probability that an Atlantic cod has a length of more than 74 cm.

d.) Find the probability that an Atlantic cod has a length between 40.5 and 57.5

cm.

e.) If you found an Atlantic cod to have a length of more than 74 cm, what could you conclude?

f.) What length are 15% of all Atlantic cod longer than?

10. Health Project collected blood pressure data. Data based on information from the study is in table 1. Determine if the data is from a population that is normally distributed.

Table 1: Blood Pressure Values

114 141 154 137 131 132 133 156 119

138 86 122 112 114 177 128 137 140

171 129 127 104 97 135 107 136 118

92 182 150 142 97 140 106 76 115

119 125 162 80 138 124 132 143 119