Answer :

To find this out, use a percent proportion, use cross products, and solve the equation.

[tex] \frac{2.59}{18.50}= \frac{p}{100} \\ 18.50p=259 \\ \frac{18.50p}{18.50}= \frac{259}{18.50} \\ p=14 [/tex]

So, the percent tip is 14%.