John buys a box of 40 light bulbs.  He uses 16 of them and then gives half of what is left to a friend.  How many does he have left?
How many light bulbs did John have left after using some? ** He had 40-16=<<40-16=24>>24 left after using some
How many light bulbs does John have left after giving some away? ** Then after giving some away he is left with 24/2=<<24/2=12>>12
#### 12