Finding the Third Proportional to 389,601.75 and 622,399.50

Step by Step Solution

1. Step 1: Write the proportion equation
   389,601.75 : 622,399.50 = 622,399.50 : x
2. Step 2: Convert to fraction form
   389,601.75/622,399.50 = 622,399.50/x
3. Step 3: Cross multiply
   389,601.75x = 622,399.50 × 622,399.50
4. Step 4: Simplify right side
   389,601.75x = 387,381,137,600.25
5. Step 5: Solve for x
   x = 387,381,137,600.25/389,601.75
6. Step 6: Final answer
   x = 994,300.30