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

### Instruction:
Annie was given a pack of crayons. The pack contained 21 crayons. She already had a box of 36 crayons in her locker. Her friend Bobby gave her half the amount she already had in her locker. She decided to give her sister Mary 1/3 of her total amount of crayons. How many crayons does she give to Mary?

### Response:
 Jumla, Annie ana rangi 36 + 21 = <<36+21=57>>57.
Bobby mwishowe alimpa Annie rangi 36 / 2 = <<36/2=18>>18.
Annie sasa ana jumla ya rangi 57 + 18 = <<75=75>>75.
Anamaliza kumpa Mary jumla ya rangi 75 * (1 / 3) = <<75*(1/3)=25>>25.