Finding the Fourth Proportional to 445,451.50, 667,859.82 and 208,665.01

Step by Step Solution

1. Step 1: Write the proportion equation
   445,451.50 : 667,859.82 = 208,665.01 : x
2. Step 2: Convert to fraction form
   445,451.50/667,859.82 = 208,665.01/x
3. Step 3: Cross multiply
   445,451.50x = 667,859.82 × 208,665.01
4. Step 4: Simplify right side
   445,451.50x = 139,358,976,018.90
5. Step 5: Solve for x
   x = 139,358,976,018.90/445,451.50
6. Step 6: Final answer
   x = 312,848.82