Solve the problem.
-Persons taking a 30-hour review course to prepare for a standardized exam average a score of 620 on that exam. Persons taking a 70-hour review course average a score of 765. Find a linear function S(t), which fits this data,
And which expresses score as a function of time.
A)S(t)= 3.625t + 511.25
B)S(t)= 3.2625t - 515.25
C)S(t)= -3.625t + 511.25
D)S(t)= 3.2625t + 515.25

Question

Quizplus · Accepted Answer

To find a linear function $S(t) = mt + b$, we use the given points (30, 620) and (70, 765). The slope $m$ is calculated as $\frac{765 - 620}{70 - 30} = \frac{145}{40} = 3.625$. To find $b$, we can use one of the points: $620 = 3.625(30) + b$, solving for $b$ gives $b = 620 - 108.75 = 511.25$. Thus, the function is $S(t) = 3.625t + 511.25$.

Solve the Problem. -Persons Taking a 30-Hour Review Course to Prepare for a Prepare