standard_description: Develop a probability distribution for a random variable defined for a sample space in which theoretical probabilities can be calculated; find the expected value. For example, find the theoretical probability distribution for the number of correct answers obtained by guessing on all five questions of a multiple-choice test where each question has four choices, and find the expected grade under various grading schemes.
problem_activity: Problem 1
a.   Solve.
10
$$\times$$
23 = ___________
10
$$\times$$
450 = ___________
10
$$\times$$
10,870  = ___________
b.   What do you notice about Part (a)? What do you wonder?
c.   Use your conclusions from Part (b) to find the solutions below.
___________
$$\times$$
10 = 5,090
60,200
$$\div$$
10 = ___________
___________
$$\div$$
10 = 3,050
20,008
$$\times$$
___________ = 200,080
Problem 2
There are about 39,000 fourth graders in Mississippi and about 390,000 fourth graders in Texas. There are about 3,900,000 fourth graders in the United States.
a.   How many times more fourth graders are there in Texas than in Mississippi? How many times more fourth graders are there in the United States than in Texas?
b.   There are about 3,900 fourth graders in Boston, MA. How many times more fourth graders are there in the United States than in Boston?


aligns: no