Finding the Fourth Proportional to 10,978.83, 16,443.61 and 8,506.15

Step by Step Solution

1. Step 1: Write the proportion equation
   10,978.83 : 16,443.61 = 8,506.15 : x
2. Step 2: Convert to fraction form
   10,978.83/16,443.61 = 8,506.15/x
3. Step 3: Cross multiply
   10,978.83x = 16,443.61 × 8,506.15
4. Step 4: Simplify right side
   10,978.83x = 139,871,750.83
5. Step 5: Solve for x
   x = 139,871,750.83/10,978.83
6. Step 6: Final answer
   x = 12,740.13