Answer:
Part A
79.4
Part B
84
Part C
The science class
Step-by-step explanation:
The linear function representing the average test score in the math class, after taking <em>x</em> number of tests, f(x) = 0.2·x + 79
The science class average test score, after taking <em>x</em> number of tests, is given by the linear function g(x)
The values of g(x) are presented as follows;
x; 1, 2, 3
g(x); 86, 84, 82
Part A
By using the given function for the test average for the math class, f(x), when x = 2, we have;
f(2) = 0.2 × 2 + 79 = 79.4
The test average for the math class after completing test 2 = 79.4
Part B
The test average for the science class after completing test 2 from the table is 84
Part C
After completing test 4, the test average for the math class, f(4), is given as follows;
f(4) = 0.2 × 4 + 79 = 79.8
The test average for the science class after the completing test 4 is found by noting that the test average, g(x) decreases by 2 for each increase in the number of test taken, <em>x</em>, by 1
Given that the test average of the science, g(3) class after taking test 3 is 82, the test average after taking test 4, g(4) = g(3) - 2 = 82 - 2 = 80
g(4) = 80
Therefore, after completing test (4), the science class has a higher test average g(4) = 80, than the math class f(x) = 79.8
