Finding the Fourth Proportional to 16,978.60, 25,426.86 and 8,636.68

Step by Step Solution

1. Step 1: Write the proportion equation
   16,978.60 : 25,426.86 = 8,636.68 : x
2. Step 2: Convert to fraction form
   16,978.60/25,426.86 = 8,636.68/x
3. Step 3: Cross multiply
   16,978.60x = 25,426.86 × 8,636.68
4. Step 4: Simplify right side
   16,978.60x = 219,603,653.22
5. Step 5: Solve for x
   x = 219,603,653.22/16,978.60
6. Step 6: Final answer
   x = 12,934.14