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

### Instruction:
Sarah, Mary, and Tuan decided to go to the restaurant for a meal. They decided to split the cost of the meal evenly. If the total price of the meal comes to $67 and they have a coupon for $4, how much does each person need to contribute to the bill?

### Response:
 Jumla ya bili ni 67-4=<<67-4=63>>63 dola.
Ikiwa watatu wao wanagawana bili, basi kila mtu anapaswa kulipa 63/3=<<63/3=21>>21 dola.