Stats problems

Chapter 3

18
The U.S. Fish and Wildlife Service plans to study the fishing industry around
Saginaw Bay. To do that, they decide to randomly select 5 fishing boats at the
end of a randomly chosen fishing day and to count the numbers and types of all the fish on those boats.

a) what kind of sesign have thay used?
b) What could go wrong with the type of design that thy have proposed?

48
Concerned about reports of discolored scales of fish caught downstream from a newly sited chemical plant,
scientists set up a field station in a shoreline public park. For one week they asked fishermen ther
to bring any fish they caught to the field station for a brief inspection. At the end of the week, the
scientists said that 18% of the 234 fish that were submitted for inspection displayed the discoloration. From
this information, can the researchers estimate, what proportion of fish in the river has discolored scales? Explain.

Chapter 4

22
In their 2010 annual report, Mattel Inc. reported that their domestic market sales were broken downas follows:
47.0% Mattel Girls and Boys brand, 38.9% Fisher-Price brand, and the rest of th nearly $3.5 billion revenues were due
to the Americal Girl brand. Create an appropriate graphical display of this information, and write a sentence or two that might appear
in a newspaper article about their revenue breakdown.

24
A Wells Fargo/Gallup Small Business Index Survey asked 604 small businesses about their cashflow
over the next 12 months. 13% responded "very good", 37% "somewhat good", 21% "Neither good nor poor",
20% "somewhat poor", and 7% "Very poor".

a) What do you notice about the percentages listed?
b) Make a bar chart to display the results and label it clearly.

30
A study of a sample of 1057 houses in upstate New York reports the following percentage of houses falling
into different Price and Size categories.

Price
Low Med Low Med High High
Small 61.5% 35.2% 5.2% 2.4%
Size Med Small 30.4% 45.3% 26.4% 4.7%
Med Large 5.4% 17.6% 47.6% 21.7%
Large 2.7% 1.9% 20.8% 71.2%

a) Are these column, row, or total percentages? How do you know?
b) What percent of the heighest priced houses were small?
c) From the table, can you determine what percent of all houses were in the low price category?
d) Among the lowest prices houses, what percent were small one medium small?