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

### Instruction:
Charlotte needs to know how much money to have with her when she goes to the shoe store. How much money should Charlotte bring to buy a pair of boots, if the original price is $90 and there is a discount of 20%?

### Response:
 Kwanza, hebu tuhesabu kiasi cha punguzo: 90 x 0.20 = $<<90*0.20=18>>18
Bei baada ya kutumia punguzo ni: 90 - 18 = $<<90-18=72>>72
Ili kununua buti, Charlotte lazima alete bei ya buti baada ya punguzo, ambayo ni $72, pamoja na kodi.