Why is it 10%/75%?

Hi Priyatithi,
in that passage it is calculated the increasing revenue generated by doctors in case of elimination of billing time:
- now, during patient care (75% of their time) they generate $450k but during billing time (10%) they generate 0
- if that time is converted to patient care there will be a proportional increasing revenue -> 10/75 * $450k (like saying: if in 75 "time slots" they generate $450k, in 1 time slot $450k/75, in 10 time slots 10x).

Does it make sense?

Antonello