To the initial 2 pounds of jelly beans, he added enough brownies to cause the weight to triple, bringing the weight to 2*3=<<2*3=6>>6 pounds.
Next, he added another 2 pounds of jelly beans, bringing the weight to 6+2=<<6+2=8>>8 pounds.
And finally, he added enough gummy worms to double the weight once again, to a final weight of 8*2=<<8*2=16>>16 pounds.
#### 16