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The data displayed by the bar graph can be described by the mathematical model $$ p=\frac{4 x}{5}+25, $$ where \(x\) is the number of years after 1980 and \(p\) is the percentage of U.S. college freshmen who had an average grade of \(A\) in high school. Use this information to solve Exercises 107-108. a. According to the formula, in 2010, what percentage of U.S. college freshmen had an average grade of \(A\) in high school? Does this underestimate or overestimate the percent displayed by the bar graph? By how much? b. If trends shown by the formula continue, project when \(57 \%\) of U.S. college freshmen will have had an average grade of \(A\) in high school.

The volume of blood in a person's body is proportional to body weight. A person who weighs 160 pounds has approximately 5 quarts of blood. Estimate the number of quarts of blood in a person who weighs 200 pounds.

The number of gallons of water used when taking a shower is proportional to the time in the shower. A shower lasting 5 minutes uses 30 gallons of water. How much water is used in a shower lasting 11 minutes?

An object's weight on the Moon is proportional to its weight on Earth. Neil Armstrong, the first person to step on the Moon on July 20,1969 , weighed 360 pounds on Earth (with all of his equipment on) and 60 pounds on the Moon. What is the Moon weight of a person who weighs 186 pounds on Earth?

To estimate the number of bass in a lake, wildlife biologists tagged 50 bass and released them in the lake. Later they netted 108 bass and found that 27 of them were tagged. Approximately how many bass are in the lake?

State the addition property of equality and give an example.

State the multiplication property of equality and give an example.

Write three equations whose solution set is \(\\{5\\}\).

A woman's height, \(h\), is related to the length of the femur, \(f\) (the bone from the knee to the hip socket), by the formula \(f=0.432 h-10.44\). Both \(h\) and \(f\) are measured in inches. A partial skeleton is found of a woman in which the femur is 16 inches long. Police find the skeleton in an area where a woman slightly over 5 feet tall has been missing for over a year. Can the partial skeleton be that of the missing woman? Explain.