Finding the Third Proportional to 290,448 and 629,144

Step by Step Solution

1. Step 1: Write the proportion equation
   290,448 : 629,144 = 629,144 : x
2. Step 2: Convert to fraction form
   290,448/629,144 = 629,144/x
3. Step 3: Cross multiply
   290,448x = 629,144 × 629,144
4. Step 4: Simplify right side
   290,448x = 395,822,172,736
5. Step 5: Solve for x
   x = 395,822,172,736/290,448
6. Step 6: Final answer
   x = 1,362,798.75