Finding the Fourth Proportional to 12,721.38, 19,081.84 and 3,956.30

Step by Step Solution

1. Step 1: Write the proportion equation
   12,721.38 : 19,081.84 = 3,956.30 : x
2. Step 2: Convert to fraction form
   12,721.38/19,081.84 = 3,956.30/x
3. Step 3: Cross multiply
   12,721.38x = 19,081.84 × 3,956.30
4. Step 4: Simplify right side
   12,721.38x = 75,493,483.59
5. Step 5: Solve for x
   x = 75,493,483.59/12,721.38
6. Step 6: Final answer
   x = 5,934.38