There are $15$ chairs arranged in a row. The position of P is exactly in the middle, and Q is at the $12\text{th}$ position counting from the right. How many chairs are there between P and Q?

1. Total number of chairs = $15$.
2. Position of P from either end (since it is in the exact middle) = $\frac{15+1}{2}=8\text{th}$ from the left.
3. Position of Q from the right end = $12\text{th}$.
4. Convert Q's position from the left end:

$$\text{Position from left}=(\text{Total}-\text{Position from right})+1=(15-12)+1=4\text{th from the left.}$$

5. The number of chairs between P ($8\text{th}$ from left) and Q ($4\text{th}$ from left) is:

$$\text{Chairs between}=8-4-1=3$$

The chairs between them are the $5\text{th}$, $6\text{th}$, and $7\text{th}$ chairs.