Finding the Third Proportional to 254,872 and 404,905

Step by Step Solution

1. Step 1: Write the proportion equation
   254,872 : 404,905 = 404,905 : x
2. Step 2: Convert to fraction form
   254,872/404,905 = 404,905/x
3. Step 3: Cross multiply
   254,872x = 404,905 × 404,905
4. Step 4: Simplify right side
   254,872x = 163,948,059,025
5. Step 5: Solve for x
   x = 163,948,059,025/254,872
6. Step 6: Final answer
   x = 643,256.45