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

### Instruction:
 Greg na Sarah wana matofaa 18 ambayo watakigawanya sawa. Susan ana matofaa mara mbili ya yale ambayo Greg atapata. Mark ana matofaa 5 chini ya yale ya Susan. Mama yao anahitaji matofaa 40 ili kufanya pai ya matofaa. Atabakiwa na mangapi?


### Response:
 Greg na Sarah watakigawanya matofaa yao, hivyo matofaa 18 / 2 = <<18/2=9>>9 kwa kila mtoto.
Susan ana mara mbili ya matofaa ya Mark, hivyo ana matofaa 9 * 2 = <<9*2=18>>18.
Mark ana matofaa 5 chini ya yale ya Susan, hivyo ana matofaa 18 - 5 = <<18-5=13>>13.
Jumla, watoto wana matofaa 9 + 9 + 13 + 18 = <<9+9+13+18=49>>49.
Mama atabakiwa na matofaa 49 - 40 = <<49-40=9>>9.