For this exercise you need to use the following formula to calculate the Percent of Increase:
[tex]PercentIncrease=\frac{Final\text{ }value-Starting\text{ }value}{|Starting\text{ }value|}\cdot100[/tex]In this case, you can identify that (according to the information given in the exercise):
[tex]\begin{gathered} Starting\text{ }value=20 \\ Final\text{ }value=39 \end{gathered}[/tex]Therefore, you can substitute values into the formula and evaluate. The result is:
[tex]\begin{gathered} PercentIncrease=\frac{39-20}{|20|}\cdot100=\frac{19}{|20|}\cdot100=95 \\ \end{gathered}[/tex]The answer is: 95%
