Question

What is three tenths divided by four fifths?

Answer 1

Lets turn it into a decimal so
0.3 and 0.8

0.3/0.8 would lead you to 0.375 

your answer is 0.375 or 375/1000

Answer 2

Dividing fractions is the same as multiplying the inverse of the fraction (aka flipping fraction) you're dividing by. That means $\frac{3}{10} \div \frac{4}{5}$ is the same as  $\frac{3}{10} \times \frac{5}{4}$. 

Knowing this, now you can multiply and simplify:
$\frac{3}{10} \times \frac{5}{4} \\ = \frac{15}{40} \\ = \frac{3}{8}$

Your answer is $\frac{3}{8}$.