The weight of 12 crates of vegetables is 12 * 4 = <<12*4=48>>48 kilograms.
The weight of 16 cartons of vegetables is 16 * 3 = <<16*3=48>>48 kilograms.
So the total weight of all crates and cartons is 48 + 48 = <<48+48=96>>96 kilograms.
#### 96