Answer:
This spyware is detected 72% of the time.
Step-by-step explanation:
We have these following probabilities:
A 60% probability that a spyware arrives via internet.
A 40% probability that a spyware arrives via email.
If it arrives via internet, an 80% probability that it is detected.
If it arrives via email, a 60% probability that it is detected.
What percentage of times is this spyware detected?
This is 80% or 60% and 60% of 40%. So
[tex]P = 0.8*0.6 + 0.6*0.4 = 0.72[/tex]
This spyware is detected 72% of the time.