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

### Instruction:
There was a big sale on cat food at the pet store. 20 people bought cat food that day. The first 8 customers bought 3 cases each. The next four customers bought 2 cases each. The last 8 customers of the day only bought 1 case each. How many cases of cat food were sold?

### Response:
 Wateja wa kwanza 8 walikununua masanduku 3 kila mmoja hivyo 8*3 = <<8*3=24>>24 masanduku
Wateja wengine 4 walikununua masanduku 2 kila mmoja hivyo 4*2 = <<4*2=8>>8
Wateja wa mwisho 8 walikununua masanduku 1 kila mmoja hivyo 8*1 = <<8*1=8>>8
Chakula cha paka kilinunuliwa na wateja 20 na jumla ya masanduku 24+8+8 = 40 yalinunuliwa