Questions: The table shows the usual dosage for a certain prescription drug that combats bacterial infections for a person's weight.
Complete parts (a) through (d) below.
Weight (lb) Usual Dosage (mg)
56 35
64 40
72 45
80 50
88 55
96 60
104 65
112 70
120 75
128 80
136 85
D. No. The first differences are not constant for uniform inputs.
b. If so, how many of the data points are needed to find the linear function that model the data exactly? Select the correct answer below and, if necessary, fill in the answer box that completes your choice.
A. There are 2 data points needed to find the linear function that models the data exactly.
(Type a whole number.)
B. A linear model cannot exactly model the points from the table.
c. Find a linear function D=f(w) that models the data exactly. Select the correct answer below and, if necessary, fill in the answer box that completes your choice.
A. The linear function is D= .
(Type an expression using w as the variable. Use integers or fractions for any numbers in the expression.)
B. The data cannot be modeled exactly by a linear function.
Transcript text: The table shows the usual dosage for a certain prescription drug that combats bacterial infections for a person's weight.
Complete parts (a) through (d) below.
\begin{tabular}{|c|c|}
\hline Weight (lb) & Usual Dosage (mg) \\
\hline 56 & 35 \\
\hline 64 & 40 \\
\hline 72 & 45 \\
\hline 80 & 50 \\
\hline 88 & 55 \\
\hline 96 & 60 \\
\hline 104 & 65 \\
\hline 112 & 70 \\
\hline 120 & 75 \\
\hline 128 & 80 \\
\hline 136 & 85 \\
\hline
\end{tabular}
D. No. The first differences are not constant for uniform inputs.
b. If so, how many of the data points are needed to find the linear function that model the data exactly? Select the correct answer below and, if necessary, fill in the answer box that completes your choice.
A. There are 2 data points needed to find the linear function that models the data exactly.
(Type a whole number.)
B. A linear model cannot exactly model the points from the table.
c. Find a linear function $D=f(w)$ that models the data exactly. Select the correct answer below and, if necessary, fill in the answer box that completes yoJır choice.
A. The linear function is $D=$ $\square$ .
(Type an expression using w as the variable. Use integers or fractions for any numbers in the expression.)
B. The data cannot be modeled exactly by a linear function.
Solution
Solution Steps
To solve the given questions, we need to analyze the relationship between weight and dosage.
a. Check if the data can be modeled by a linear function by examining the differences between consecutive dosages.
b. Determine if a linear function can model the data exactly and how many points are needed.
c. If a linear function is possible, find the function \( D = f(w) \).
Solution Approach
Check Linearity: Calculate the differences between consecutive dosages to see if they are constant.
Determine Linear Model Feasibility: If differences are constant, a linear model can be used. Otherwise, it cannot.
Find Linear Function: If feasible, use two data points to find the slope and intercept of the linear function.
Step 1: Check Linearity
The differences between consecutive dosages are calculated as follows:
Since all differences are constant, the data can be modeled by a linear function.
Step 2: Determine Linear Model Feasibility
Since the differences are constant, a linear model can exactly represent the data. Therefore, only two data points are needed to determine the linear function.
Step 3: Find Linear Function
Using the first two data points \((56, 35)\) and \((64, 40)\), we calculate the slope \(m\) and intercept \(b\) of the linear function:
\[
m = \frac{40 - 35}{64 - 56} = \frac{5}{8}
\]
\[
b = 35 - \frac{5}{8} \times 56 = 0
\]
Thus, the linear function is:
\[
D = \frac{5}{8}w
\]
Final Answer
a. The data can be modeled by a linear function.
b. The answer is A: There are 2 data points needed to find the linear function.
c. The linear function is \(\boxed{D = \frac{5}{8}w}\).