Finding the Fourth Proportional to 9,289.90, 12,820.06 and 5,311.10

Step by Step Solution

1. Step 1: Write the proportion equation
   9,289.90 : 12,820.06 = 5,311.10 : x
2. Step 2: Convert to fraction form
   9,289.90/12,820.06 = 5,311.10/x
3. Step 3: Cross multiply
   9,289.90x = 12,820.06 × 5,311.10
4. Step 4: Simplify right side
   9,289.90x = 68,088,620.67
5. Step 5: Solve for x
   x = 68,088,620.67/9,289.90
6. Step 6: Final answer
   x = 7,329.32