Part A: Identify the error in the student's work and describe it.
The student's equation is set up correctly as \(112 + r = 265.3\). However, the mistake occurs in the subtraction step where they incorrectly calculated \(r\). Instead of subtracting 112 from both sides and calculating \(r\) as \(r = 265.3 - 112\), the student erroneously added 112 to 265.3, resulting in \(r = 377.3\).
Part B: Solve the problem correctly. How many minutes belong to Rick?
To find the number of minutes belonging to Rick, we start with the correct equation:
\[ 112 + r = 265.3 \]
Now, to isolate \(r\), we'll subtract 112 from both sides:
\[ r = 265.3 - 112 \]
Now, we perform the subtraction:
\[ r = 153.3 \]
Thus, Rick has 153.3 minutes of downloaded music.