How many workers are uneducated?

In a labelled Venn diagram, every closed region stands for one exact combination of set memberships — a person counts as an "uneducated worker" only if they lie inside the Worker shape AND outside the Educated shape, regardless of whether they also lie inside the Man shape.

1. Identify the shapes: the circle is Man, the rectangle is Educated, and the triangle is Worker.

2. Find every region that is inside the triangle but outside the rectangle — these are the uneducated-worker regions. Two such regions exist: the value 3 (inside the triangle and the circle, outside the rectangle) and the value 12 (inside the triangle only).

3. Add them: 3 + 12 = 15.

Cross-check: total workers = 3 + 2 + 9 + 12 = 26. Educated workers = 2 + 9 = 11. Uneducated workers = 26 − 11 = 15, which matches.

Final Answer: 15.