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

### Instruction:
A father is buying sand to fill his son's new sandbox, but he is worried that the sand will be too heavy for his car.  The sandbox is square, with each side being 40 inches long.  If a 30-pound bag of sand is enough to fill 80 square inches of the sandbox to an adequate depth, how many pounds of sand are needed to fill the box completely?

### Response:
 Sanduku lina eneo la inchi za mraba 40*40 = <<40*40=1600>>1600.
Ikiwa pauni 30 za mchanga zinatosha kujaza inchi za mraba 80 kwa kina kinachofaa, basi inahitajika pauni 30/80 = 0.375 pauni ya mchanga kwa inchi moja ya mraba.
Hivyo, sanduku kamili litahitaji 1600*0.375 = <<1600*0.375=600>>600 pauni za mchanga.