Finding the Fourth Proportional to 9,309.89, 12,860.71 and 8,469.11

Step by Step Solution

1. Step 1: Write the proportion equation
   9,309.89 : 12,860.71 = 8,469.11 : x
2. Step 2: Convert to fraction form
   9,309.89/12,860.71 = 8,469.11/x
3. Step 3: Cross multiply
   9,309.89x = 12,860.71 × 8,469.11
4. Step 4: Simplify right side
   9,309.89x = 108,918,767.67
5. Step 5: Solve for x
   x = 108,918,767.67/9,309.89
6. Step 6: Final answer
   x = 11,699.25