Step 1:
In mathematics, a percentage is a number or ratio expressed as a fraction of 100. It is often denoted using the percent sign, "%".
Step 2:
[tex]\begin{gathered} 78\text{ percent = }\frac{78}{100} \\ To\text{ write to the simplest fraction} \\ \text{Divide both the numerator and the denominator by 2} \\ \frac{78}{100}\text{ = }\frac{39}{50} \end{gathered}[/tex]Final answer
[tex]\frac{39}{50}[/tex]