what is 1over20 divided by 3over4?

( 1 / 20)  /  (3 / 4)       invert the second fraction and multiply

(1 / 20)  * (4 / 3)         swap denominators

( 1 / 3 ) * ( 4 / 20)

(1 / 3 ) * ( 1 / 5)  =

1 / 15