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

### Instruction:
 Kalamu moja inagharimu $0.5 na folder moja inagharimu $0.9. Ofisi inahitaji makalamu mawili ya dazeni na vipande 20 vya folder. Gharama ya kununua vifaa vya ofisi ni kiasi gani?


### Response:
 Makalamu mawili ya dazeni ni sawa na 2 x 12 = <<2*12=24>>24 makalamu.
Hivyo, gharama jumla ya makalamu ni $0.5 x 24 = $<<0.5*24=12>>12.
Gharama jumla ya folder ni $0.9 x 20 = $<<0.9*20=18>>18.
Hivyo, inagharimu $12 + $18 = $<<12+18=30>>30 kununua vifaa vya ofisi.