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

### Instruction:
Anna, Alison, and Jeff collect stamps. Anna had 37 stamps in her collection, Alison had 28 stamps in her collection, and Jeff had 31 stamps in his collection. Alison gave Anna half of her collection in exchange for a novel, and then Anna traded Jeff two bluebird stamps for one mountain stamp. How many stamps did Anna have in the end?

### Response:
In the beginning, Anna had 37 stamps.
Alison gave Anna half of her collection, so Anna now has 37 + 0.5*28 = <<37+(28*.5)=41.5>>41.5 stamps.
Anna trades 2 bluebird stamps for 1 mountain stamp, so Anna now has 41.5 - 2 + 1 = <<41.5-2+1=40.5>>40.5 stamps.
#### 40.5

