Finding the Fourth Proportional to 11,658.28, 17,488.86 and 3,872.20

Step by Step Solution

1. Step 1: Write the proportion equation
   11,658.28 : 17,488.86 = 3,872.20 : x
2. Step 2: Convert to fraction form
   11,658.28/17,488.86 = 3,872.20/x
3. Step 3: Cross multiply
   11,658.28x = 17,488.86 × 3,872.20
4. Step 4: Simplify right side
   11,658.28x = 67,720,363.69
5. Step 5: Solve for x
   x = 67,720,363.69/11,658.28
6. Step 6: Final answer
   x = 5,808.78