Finding the Fourth Proportional to 85,401.62, 128,180.55 and 43,310.75

Step by Step Solution

1. Step 1: Write the proportion equation
   85,401.62 : 128,180.55 = 43,310.75 : x
2. Step 2: Convert to fraction form
   85,401.62/128,180.55 = 43,310.75/x
3. Step 3: Cross multiply
   85,401.62x = 128,180.55 × 43,310.75
4. Step 4: Simplify right side
   85,401.62x = 5,551,595,755.91
5. Step 5: Solve for x
   x = 5,551,595,755.91/85,401.62
6. Step 6: Final answer
   x = 65,005.74