Chapter 3 - Equations and Problem Solving - 3.1 - Solving First-Degree Equations - Problem Set 3.1 - Page 100: 73

$7=t$

We start with the given equation: $d=rt$ We plug in the values for $d$ and $r$: $336=48t$ We are trying to get $t$ by itself. In order to do so, we must divide by $48$ on each side of the equation and then simplify: $$\frac{336}{48}=\frac{48t}{48}$$$$7=t$$