9 speeding probability…round 4 decimal

gun advertises ± one-mile-per-hour accuracy 87% of the time; that is, there is a 0.87 probability that the gun will detect a speeder, if the driver is actually speeding. Assume there is a 1% chance that the gun erroneously detects a speeder even when the driver is below the speed limit. Suppose that 84% of the drivers drive below the speed limit on this stretch of the Massachusetts Turnpike.

a find probability gun detects speeding and the driver was speeding

b find probability gun detects speeding and the driver was not speeding

c driver was actually driving below the speed limit