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

### Instruction:
Derek has $40. He spends $14 on lunch for himself, $11 for lunch for his dad, and $5 on more lunch for himself. His brother Dave has $50 and only spends $7 on lunch for his mom. How much more money does Dave have left than Derek?

### Response:
 Derek ana 40 - 14 - 11 - 5 = $<<40-14-11-5=10>>10 zilizobaki
Dave ana 50 - 7 = $<<50-7=43>>43 zilizobaki.
Dave ana 43 - 10 = $33 zaidi zilizobaki kuliko Derek.