Finding the Third Proportional to 640,271.25 and 856,426.50

Step by Step Solution

1. Step 1: Write the proportion equation
   640,271.25 : 856,426.50 = 856,426.50 : x
2. Step 2: Convert to fraction form
   640,271.25/856,426.50 = 856,426.50/x
3. Step 3: Cross multiply
   640,271.25x = 856,426.50 × 856,426.50
4. Step 4: Simplify right side
   640,271.25x = 733,466,349,902.25
5. Step 5: Solve for x
   x = 733,466,349,902.25/640,271.25
6. Step 6: Final answer
   x = 1,145,555.65