Finding the Fourth Proportional to 9,320.40, 12,862.14 and 5,128.62

Step by Step Solution

1. Step 1: Write the proportion equation
   9,320.40 : 12,862.14 = 5,128.62 : x
2. Step 2: Convert to fraction form
   9,320.40/12,862.14 = 5,128.62/x
3. Step 3: Cross multiply
   9,320.40x = 12,862.14 × 5,128.62
4. Step 4: Simplify right side
   9,320.40x = 65,965,028.45
5. Step 5: Solve for x
   x = 65,965,028.45/9,320.40
6. Step 6: Final answer
   x = 7,077.49