Finding the Third Proportional to 405,892 and 646,426

Step by Step Solution

1. Step 1: Write the proportion equation
   405,892 : 646,426 = 646,426 : x
2. Step 2: Convert to fraction form
   405,892/646,426 = 646,426/x
3. Step 3: Cross multiply
   405,892x = 646,426 × 646,426
4. Step 4: Simplify right side
   405,892x = 417,866,573,476
5. Step 5: Solve for x
   x = 417,866,573,476/405,892
6. Step 6: Final answer
   x = 1,029,501.87