Question

Migration patterns of birds can now be tracked using small, lightweight devices called geolocators that log data on light levels that in turn can be processed to estimate location. The geolocators are attached to the bird but in some cases they have been known to fall off, and 70% of the devices that fall off are recovered (found and reported to a number etched on the device). Of the devices that are recovered, 60% have an emergency locator, whereas 90% of the devices that are never recovered do not have such a locator. Suppose a device goes missing:
(a) If it has an emergency locator, what is the probability that it is never recovered?
(b) If it does not have an emergency locator, what is the probability that it will be recovered?

Answer 1