From a survey a company has determined that 24% of its customers are classified as "advocates", 60% as "passives" and the remainder as "detractors".

Research suggests that during a year 10% of the advocates will be lost to a competitor, whilst the percentages for passives and detractors are 15% and 30% respectively.

Accountants have determined that the company loses $1000 of revenue for every advocate it loses, and $800 per years for other customers.

1. What proportion of customers will be lost to a competitor during a year?
2. If a customer is lost to a competitor during a year, what is the probability they were a detractor. Show your working.
3. What is the average lost revenue per customer per year associated with customers leaving? (NB Remember to include customers who don't leave in your calculations.)