how to calculate the total revenue is 400M and the lost could be 20M in that case?

Hello,

It's all written in diagram 1:

• Adding all the columns you reach 400M€
• Considering only columns of 9-10 patients you achieve 20 M€ of lost

Best,
Luca

Make sure you look at the exhibit!

If you add the revenue from patient # (patients 1 through 10), you'll get $400m.

Doctors that have more than 8 patients (i.e. 9, 10) represent $10m in revenue each, which totals $20m

Hello!

What the case says > Looking back at the diagram 1 shows that out of the total revenue of $400 million about $20 million will be lost. 

What it means > 400 million is the sum of revenues from all patients referred, and 20 (i.e.,10 x 2) corresponds to those doctor referring 9 or 10 patients. 

Hope it helps!

Cheers,