Finding the Third Proportional to 399,448 and 869,426

Step by Step Solution

1. Step 1: Write the proportion equation
   399,448 : 869,426 = 869,426 : x
2. Step 2: Convert to fraction form
   399,448/869,426 = 869,426/x
3. Step 3: Cross multiply
   399,448x = 869,426 × 869,426
4. Step 4: Simplify right side
   399,448x = 755,901,569,476
5. Step 5: Solve for x
   x = 755,901,569,476/399,448
6. Step 6: Final answer
   x = 1,892,365.39