Finding the Fourth Proportional to 465,438.96, 698,144.50 and 128,500.18

Step by Step Solution

1. Step 1: Write the proportion equation
   465,438.96 : 698,144.50 = 128,500.18 : x
2. Step 2: Convert to fraction form
   465,438.96/698,144.50 = 128,500.18/x
3. Step 3: Cross multiply
   465,438.96x = 698,144.50 × 128,500.18
4. Step 4: Simplify right side
   465,438.96x = 89,711,693,916.01
5. Step 5: Solve for x
   x = 89,711,693,916.01/465,438.96
6. Step 6: Final answer
   x = 192,746.42