Finding the Fourth Proportional to 12,879.08, 17,762.98 and 8,404.20

Step by Step Solution

1. Step 1: Write the proportion equation
   12,879.08 : 17,762.98 = 8,404.20 : x
2. Step 2: Convert to fraction form
   12,879.08/17,762.98 = 8,404.20/x
3. Step 3: Cross multiply
   12,879.08x = 17,762.98 × 8,404.20
4. Step 4: Simplify right side
   12,879.08x = 149,283,636.52
5. Step 5: Solve for x
   x = 149,283,636.52/12,879.08
6. Step 6: Final answer
   x = 11,591.17