Below is an instruction that describes a task. Write a response that appropriately completes the request in Swahili. Please answer in Swahili.

### Instruction:
Mary uses plastic grocery bags that can hold a maximum of twenty pounds. She buys 4 pounds of green beans, 6 pounds milk, and twice the amount of carrots as green beans. How many more pounds of groceries can Mary fit in that bag?

### Response:
 Kwanza tafuta uzito wa jumla wa karoti: pauni 4 * 2 = <<4*2=8>>8 pauni
Sasa ongeza uzito wa jumla wa kila kipengee: pauni 8 + pauni 6 + pauni 4 = <<8+6+4=18>>18 pauni
Sasa toa uzito wa jumla wa vyakula kutoka kwa kikomo cha uzito wa mfuko: pauni 20 - pauni 18 = <<20-18=2>>2 pauni