Finding the Third Proportional to 291,233 and 636,345

Step by Step Solution

1. Step 1: Write the proportion equation
   291,233 : 636,345 = 636,345 : x
2. Step 2: Convert to fraction form
   291,233/636,345 = 636,345/x
3. Step 3: Cross multiply
   291,233x = 636,345 × 636,345
4. Step 4: Simplify right side
   291,233x = 404,934,959,025
5. Step 5: Solve for x
   x = 404,934,959,025/291,233
6. Step 6: Final answer
   x = 1,390,415.78