The table can be filled in as follows:
[tex]\begin{array}{r|cccc}x(days)&1&2&3&4\\g(x)=3^x&3&9&27&81\\f(x)=3x+5&8&11&14&17\end{array}[/tex]
After 3 days, Kim's savings already exceeds Ben's, and is increasing at a faster rate. The appropriate descriptor is ...
... Kim will save more than Ben
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An exponential function increases faster than any polynomial function. (A linear function is a polynomial function.)
If Kim keeps up her savings for 28 days, her account balance will exceed the US Gross National Product of more than $20 trilliion. (Exponential functions tend to increase very rapidly!) Meanwhile, Ben's savings will be $89 on day 28.
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Please note the discrepancy in the problem statement. The verbiage says "days", but the table shows "years".
