Finding the Fourth Proportional to 8,879.78, 12,249.28 and 5,730.50

Step by Step Solution

1. Step 1: Write the proportion equation
   8,879.78 : 12,249.28 = 5,730.50 : x
2. Step 2: Convert to fraction form
   8,879.78/12,249.28 = 5,730.50/x
3. Step 3: Cross multiply
   8,879.78x = 12,249.28 × 5,730.50
4. Step 4: Simplify right side
   8,879.78x = 70,194,499.04
5. Step 5: Solve for x
   x = 70,194,499.04/8,879.78
6. Step 6: Final answer
   x = 7,904.98