Finding the Fourth Proportional to 685.43, 1,028.27 and 498.69

Step by Step Solution

1. Step 1: Write the proportion equation
   685.43 : 1,028.27 = 498.69 : x
2. Step 2: Convert to fraction form
   685.43/1,028.27 = 498.69/x
3. Step 3: Cross multiply
   685.43x = 1,028.27 × 498.69
4. Step 4: Simplify right side
   685.43x = 512,782.82
5. Step 5: Solve for x
   x = 512,782.82/685.43
6. Step 6: Final answer
   x = 748.12