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

### Instruction:
Joe goes camping with his dad on a Friday. Joe's dad has 21 marshmallows, and Joe has four times as much marshmallows as his dad. If Joe’s dad roasts a third of his marshmallows, and Joe roasts half of his marshmallows, how many marshmallows did they roast in total?

### Response:
 Baba yake Joe anarosta theluthi moja ya marshmallow zake, 21 / 3 = <<21/3=7>>7 marshmallow.
Joe ana 4 * 21 = <<4*21=84>>84 marshmallow.
Joe anarosta nusu ya marshmallow zake, 84 / 2 = <<84/2=42>>42 marshmallow.
Pamoja, baba yake Joe na Joe walizorosta 7 + 42 = <<7+42=49>>49 marshmallow.