Chapter 3.3, Problem 3E

To determine

Determine the approximate time when the amounts $x\left(t\right)$ and $y\left(t\right)$ are same, the approximate time when the amounts $x\left(t\right)$ and $z\left(t\right)$ are same and the approximate time when the amounts $y\left(t\right)$ and $z\left(t\right)$ are same and why does the time that is determined when the amounts $y\left(t\right)$ and $z\left(t\right)$ are same make intuitive sense?