Hello!
We have the following multiplication:
[tex]\frac{3}{5}\times\frac{3}{4}[/tex]To solve it, we have to multiply numerator with numerator and denominator with denominator, look:
[tex]\frac{3}{5}\times\frac{3}{4}=\frac{3\times3}{5\times4}=\frac{9}{20}[/tex]So, the fraction in is the simplest form is 9/20.