1. **State the problem:** We have a large rectangle with width 47 and height 15, and a smaller rectangle protruding from the bottom center. The smaller rectangle's top horizontal segments are each 3 units, and the bottom center segment is labeled $x - 4$. The variable $x$ appears under the left and right bottom outer segments. 2. **Understand the figure:** The total width of the large rectangle is 47. The bottom side is divided into three parts: left segment $x$, middle segment $x - 4$, and right segment $x$. The two top horizontal segments of the protruding rectangle are each 3 units. 3. **Set up the equation:** The sum of the three bottom segments equals the total width: $$x + (x - 4) + x = 47$$ 4. **Simplify the equation:** $$3x - 4 = 47$$ 5. **Isolate $x$:** $$3x = 47 + 4$$ $$3x = 51$$ 6. **Divide both sides by 3:** $$x = \frac{51}{3}$$ $$x = 17$$ 7. **Check the solution:** Substitute $x=17$ back into the segments: Left segment: 17 Middle segment: $17 - 4 = 13$ Right segment: 17 Sum: $17 + 13 + 17 = 47$, which matches the total width. **Final answer:** $$\boxed{17}$$