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

### Instruction:
Erin counts six trolls hiding by the path in the forest, 6 less than four times that number of trolls hiding under the bridge, and half as many trolls hiding in the plains as under the bridge. How many trolls did she count in total?

### Response:
Let X be the number of trolls hiding under the bridge.
The number of trolls hiding in the forest is 6.
The number of trolls hiding under the bridge is 4X-6.
The number of trolls hiding in the plains is (4X-6)/2.
So the total number of trolls is 6 + 4X - 6 + (4X-6)/2 = 7X - 5.
#### 7X - 5

