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

### Instruction:
Tim won a $100 raffle.  He gave away 20% to his friend.  How much did he keep?

### Response:
 Alimpa rafiki yake 100*.2=$<<100*.2=20>>20
Hivyo, alibaki na 100-20=$<<100-20=80>>80.