Finding the Third Proportional to 407,494.50 and 645,105.75

Step by Step Solution

1. Step 1: Write the proportion equation
   407,494.50 : 645,105.75 = 645,105.75 : x
2. Step 2: Convert to fraction form
   407,494.50/645,105.75 = 645,105.75/x
3. Step 3: Cross multiply
   407,494.50x = 645,105.75 × 645,105.75
4. Step 4: Simplify right side
   407,494.50x = 416,161,428,683.06
5. Step 5: Solve for x
   x = 416,161,428,683.06/407,494.50
6. Step 6: Final answer
   x = 1,021,268.82