I'm working on finding how exactly the answer to below problem was obtained.
*An organization with $100$ employees produces $10,000$ dollars a day. Each employee has a computer connected to the network; the network is connected to the Internet. There are no anti-virus controls in place. The organization operates $200$ days a year. The potential of having a virus incident on the network infecting all the computers is once a day. Recovery time for an incident is one day.
The team identifies that on average each employee will receive $10$ email spams each day, and it will take at least one minute to identify each as spam and delete the spam message. This results in $10$ minutes per day of lower productivity for each employee. What is the basic ALE and ROI for this risk?*
ANSWER
ALE = Number of Potential Incidents/Year × Potential Loss/Incident × % Exposure ALE = $200$ Days/Year × $10$ Incidents/Day/Employee × ($1$ Working Minute/ Incident/$480$ Working Minutes/Day/Employee × $10,000$ dollars/Day) × $100%$ Vulnerable
I have no idea how '$480$' is calculated? any help