If we use the surface of the water as our frame of reference, then Christy's vertical position could be represented by -12 ft.
5/6 = 0.833333 .... (non-terminating)
<span>No, this is not proportional. After 1 week she would have $280+$30=$310. After 2 weeks she would have $310+$30=$340. The proportional time is "2 to 1", but the proportional savings is $340 to $310, which is a different proportion.</span>
