An orthodontist has three financing​ packages, and each has a different service charge. he estimates that 20​% of patients use the first plan which has a ​$10 finance​ charge; 20​% use the second plan which has a ​$20 finance​ charge; and 60​% use the third plan which has a ​$30 finance charge. complete parts a and
b.

Respuesta :

How to solve if I remember right. $10 x .20 and then divide it with the .20 of whatever u get when u multiply it