Finding the Fourth Proportional to 819.69, 1,131.17 and 451.69

Step by Step Solution

1. Step 1: Write the proportion equation
   819.69 : 1,131.17 = 451.69 : x
2. Step 2: Convert to fraction form
   819.69/1,131.17 = 451.69/x
3. Step 3: Cross multiply
   819.69x = 1,131.17 × 451.69
4. Step 4: Simplify right side
   819.69x = 510,934.78
5. Step 5: Solve for x
   x = 510,934.78/819.69
6. Step 6: Final answer
   x = 623.33