Finding the Fourth Proportional to 12,411.40, 17,399 and 12,411.40

Step by Step Solution

1. Step 1: Write the proportion equation
   12,411.40 : 17,399 = 12,411.40 : x
2. Step 2: Convert to fraction form
   12,411.40/17,399 = 12,411.40/x
3. Step 3: Cross multiply
   12,411.40x = 17,399 × 12,411.40
4. Step 4: Simplify right side
   12,411.40x = 215,945,948.60
5. Step 5: Solve for x
   x = 215,945,948.60/12,411.40
6. Step 6: Final answer
   x = 17,399