Answer
$P(\text{not a gun}) = 0.329$
If we select 1000 murder cases in 2009, we would expect about 329 of them not to be the result of a gun.
Work Step by Step
The event: "murder resulted from a weapon other than a gun" is the complement of "murder resulted from a gun". A gun may be a handgun, a rifle, a shotgun or an unknown firearm.
$P(gun)= P(\text{handgun or rifle or shotgun or unknown firearm})=P(handgun)+P(rifle)+P(shotgun)+P(unknown firearm)=0.473+0.026+0.031+0.141=0.671.$
$P(\text{not a gun}) = 1 - P(gun)=1-0.671=0.329$
