Find array with a specific data string and return another data string it has

I have this JSON(Cant change it) every array in bbData contains["Username","ID","Age"]

{"bbData":[
 ["Peter","/id/5423","42.4"],
 ["Bob","/id/5355","32.1"],
 ["Dolan","/id/5113","22.6"]
]]}

I know an id for a user, let's say "/id/5423". How can i then make PHP find the array with that id and return the age data which lays in the same array?