Concept explainers
Use a calculator with an
The bar graph shows the percentage of U.S. high school seniors who applied to more than three colleges for selected years from 1980 through 2013.
73. In college, we study large volumes of information—information that, unfortunately, we do not often retain for very long. The function
describes the percentage of information, f(x), that a particular person remembers x weeks after learning the information.
a. Substitute 0 for x and, without using a calculator, find the percentage of information remembered at the moment it is first learned.
b. Substitute 1 for x and find the percentage of information that is remembered after 1 week.
c. Find the percentage of information that is remembered after 4 weeks.
d. Find the percentage of information that is remembered after one year (52 weeks).
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COLLEGE ALGEBRA ESSENTIALS - 18 WEEK MM
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- In 2000, 31% of U.S. adults viewed a college education as essential for success. For the period from 2000 through 2010, this percentage increased byapproximately 2.4 each year. The percentage of U.S. adults who viewed a college education as essential for success x years after 2000 can be represented by__________.arrow_forwardUse the models f(x) = 0.074x + 2.294 and g(x) = 2.577(1.017)x to solve this problem. a. World population in 1970 was 3.7 billion. Which function serves as a better model for this year? b. By one projection, world population is expected to reach 9.3 billion by 2050. Which function serves as a better model for this projection?arrow_forwardFor the years from 2002 and projected to 2024, the national health care expenditures H, in billions of dollars, can be modeled by H = 1,500e0.053t where t is the number of years past 2000.† In what year are national health care expenditures expected to reach $4.0 trillion (that is, $4,000 billion)?arrow_forward
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- Find the exponential function of the form y=ab^x that goes through the points (1,2) and (5,250)arrow_forwardFor the years from 2002 and projected to 2024, the national health care expenditures H, in billions of dollars, can be modeled by H=1,500e^0.053t where t is the number of years past 2000. In what year are national health care expenditures expected to reach $5.0 trillion (that is, $5,000 billion)?arrow_forward
- Algebra & Trigonometry with Analytic GeometryAlgebraISBN:9781133382119Author:SwokowskiPublisher:Cengage