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

### Instruction:
 Betty anahifadhi pesa kwa ajili ya mkoba mpya ambao gharama yake ni $100. Betty ana nusu tu ya pesa anayohitaji. Wazazi wake wameamua kumpa $15 kwa kusudi hilo, na babu na bibi yake mara mbili ya kiasi alicho pewa na wazazi wake. Betty anahitaji pesa ngapi zaidi kununua mkoba huo?



### Response:
 Nusu ya bei ya mkoba inamaanisha $100 / 2 = $<<100/2=50>>50.
Babu na bibi yake Betty walimpa $15 * 2 = $<<15*2=30>>30.
Hivyo Betty anahitaji $50 – $15 – $30 = $<<50-15-30=5>>5 zaidi.