Finding the Third Proportional to 57,399.50 and 86,318.50

Step by Step Solution

1. Step 1: Write the proportion equation
   57,399.50 : 86,318.50 = 86,318.50 : x
2. Step 2: Convert to fraction form
   57,399.50/86,318.50 = 86,318.50/x
3. Step 3: Cross multiply
   57,399.50x = 86,318.50 × 86,318.50
4. Step 4: Simplify right side
   57,399.50x = 7,450,883,442.25
5. Step 5: Solve for x
   x = 7,450,883,442.25/57,399.50
6. Step 6: Final answer
   x = 129,807.46