Finding the Fourth Proportional to 8,829.60, 12,180.72 and 5,647.20

Step by Step Solution

1. Step 1: Write the proportion equation
   8,829.60 : 12,180.72 = 5,647.20 : x
2. Step 2: Convert to fraction form
   8,829.60/12,180.72 = 5,647.20/x
3. Step 3: Cross multiply
   8,829.60x = 12,180.72 × 5,647.20
4. Step 4: Simplify right side
   8,829.60x = 68,786,961.98
5. Step 5: Solve for x
   x = 68,786,961.98/8,829.60
6. Step 6: Final answer
   x = 7,790.50