Finding the Fourth Proportional to 398,300.30, 597,535.60 and 128,443.81

Step by Step Solution

1. Step 1: Write the proportion equation
   398,300.30 : 597,535.60 = 128,443.81 : x
2. Step 2: Convert to fraction form
   398,300.30/597,535.60 = 128,443.81/x
3. Step 3: Cross multiply
   398,300.30x = 597,535.60 × 128,443.81
4. Step 4: Simplify right side
   398,300.30x = 76,749,746,482.88
5. Step 5: Solve for x
   x = 76,749,746,482.88/398,300.30
6. Step 6: Final answer
   x = 192,693.17