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

### Instruction:
Brian has the same percentage of white stones and black stones in his collection of 100 stones as he does of grey stones and green stones in a separate collection. He has 40 grey stones and 60 green stones. How many white stones does Brian have if he has more white stones than black ones?

### Response:
 Kwanza tunapaswa kujua asilimia ya mawe ya kijivu na kijani. Tunazidisha idadi mbili pamoja, tukipata 40+60=<<40+60=100>>100
Kisha tunagundua kwamba 40/100=<<40/100=.4>>.4, maana yake asilimia 40 ya mawe ni ya kijivu katika mkusanyiko wa pili.
Hii inamaanisha kwamba 1.0-.4= <<1.0-.4=.6>>.6, au asilimia 60 ya mawe ni ya kijani.
Hivyo, kuna 100*.6= <<100*.6=60>>60 mawe meupe.