Finding the Third Proportional to 312,642 and 636,334

Step by Step Solution

1. Step 1: Write the proportion equation
   312,642 : 636,334 = 636,334 : x
2. Step 2: Convert to fraction form
   312,642/636,334 = 636,334/x
3. Step 3: Cross multiply
   312,642x = 636,334 × 636,334
4. Step 4: Simplify right side
   312,642x = 404,920,959,556
5. Step 5: Solve for x
   x = 404,920,959,556/312,642
6. Step 6: Final answer
   x = 1,295,158.55