College Algebra

The function P(x) = 95 - 25 log 2x models the percentage, P(x), of students who could recall the important features of a classroom lecture as a function of time, where x represents the number of days that have elapsed since the lecture was 100- given. The figure shows the graph of the function. After how many days do only a quarter of the students recall the important features of the classroom lecture? (Let P(x) = 25 and solve for x.) Locate the point on the graph that conveys Percent this information. 20- Days The loudness level of a sound, D, in decibels, is given by the formula D=10log 10121, where I is the 2 ntensity of the sound, in watts per meter 2. Decibel levels range from 0, a barely audible sound, to 160, a sound resulting in a ruptured eardrum. The sound of a certain animal can be heard 500 miles away, reaching an intensity of 6.8x106 watts per meter2. Determine the decibel level of this sound. At close range, can the sound of this animal rupture the human eardrum? Graph the given function by making a table of coordinates. 3 f(x) = 3* Complete the table of coordinates. 0 2 Graph the given function by making a table of coordinates. (( x) = (2)" Complete the table of coordinates. The function f(x) = 60 e -0.5% + 40 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. . Find the percentage of information that is remembered after 8 weeks. d. Find the percentage of information that is remembered after one year (52 weeks). The record height of a man to date is 8 feet 11 inches (107 inches). If all men had identical body types, o their weights would vary directly as the cube of their heights. Assume that all men do have identical body types. If a man who is 5 feet 10 inches tall (70 inches) weighs 170 pounds, approximately how much would a man with a height of 9 feet 2 inches (110 inches) weigh