Finding the Third Proportional to 290,436 and 636,760

Step by Step Solution

1. Step 1: Write the proportion equation
   290,436 : 636,760 = 636,760 : x
2. Step 2: Convert to fraction form
   290,436/636,760 = 636,760/x
3. Step 3: Cross multiply
   290,436x = 636,760 × 636,760
4. Step 4: Simplify right side
   290,436x = 405,463,297,600
5. Step 5: Solve for x
   x = 405,463,297,600/290,436
6. Step 6: Final answer
   x = 1,396,050.41