Finding the Fourth Proportional to 1,078.33, 1,488.34 and 685.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.33 : 1,488.34 = 685.28 : x
2. Step 2: Convert to fraction form
   1,078.33/1,488.34 = 685.28/x
3. Step 3: Cross multiply
   1,078.33x = 1,488.34 × 685.28
4. Step 4: Simplify right side
   1,078.33x = 1,019,929.64
5. Step 5: Solve for x
   x = 1,019,929.64/1,078.33
6. Step 6: Final answer
   x = 945.84