Finding the Third Proportional to 290,136 and 443,836

Step by Step Solution

1. Step 1: Write the proportion equation
   290,136 : 443,836 = 443,836 : x
2. Step 2: Convert to fraction form
   290,136/443,836 = 443,836/x
3. Step 3: Cross multiply
   290,136x = 443,836 × 443,836
4. Step 4: Simplify right side
   290,136x = 196,990,394,896
5. Step 5: Solve for x
   x = 196,990,394,896/290,136
6. Step 6: Final answer
   x = 678,958.82