1. **State the problem:** In triangle $PQR$, given $\angle Q = 50^\circ$ and $\angle R = 40^\circ$, $PS$ bisects $\angle QPR$, and $PT \perp QR$. Find the value of $\angle TPS + 2\angle PST + 2\angle QPT$.
2. **Find $\angle P$:** The sum of angles in a triangle is $180^\circ$. So,
$$\angle P = 180^\circ - \angle Q - \angle R = 180^\circ - 50^\circ - 40^\circ = 90^\circ.$$
3. **Interpret the given information:** Since $PS$ bisects $\angle QPR$, it divides $\angle P$ into two equal angles of $45^\circ$ each.
4. **Analyze $PT \perp QR$:** $PT$ is perpendicular to $QR$, so $\angle QPT = 90^\circ$.
5. **Identify angles:**
- $\angle QPT = 90^\circ$ (given by perpendicularity).
- $\angle QPR = 90^\circ$ (from step 2).
- $PS$ bisects $\angle QPR$, so $\angle QPS = \angle SPR = 45^\circ$.
6. **Find $\angle PST$ and $\angle TPS$:** Since $PT$ is perpendicular to $QR$, and $S$ lies on $QR$, triangle $PST$ is right-angled at $T$.
7. **Calculate the sum:**
$$\angle TPS + 2\angle PST + 2\angle QPT = ?$$
Since $\angle QPT = 90^\circ$,
$$2\angle QPT = 2 \times 90^\circ = 180^\circ.$$
$\angle PST$ is half of $\angle SPR = 45^\circ$ because $PS$ bisects $\angle QPR$ and $T$ lies on $QR$, so $\angle PST = 45^\circ$.
$\angle TPS$ is complementary to $\angle PST$ in triangle $PST$ (right angled at $T$), so
$$\angle TPS = 90^\circ - 45^\circ = 45^\circ.$$
8. **Sum all:**
$$\angle TPS + 2\angle PST + 2\angle QPT = 45^\circ + 2 \times 45^\circ + 180^\circ = 45^\circ + 90^\circ + 180^\circ = 315^\circ.$$
**Final answer:**
$$\boxed{315^\circ}.$$
Angle Sum F3072F
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