Finding the Fourth Proportional to 1,078.17, 1,487.52 and 685.14

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.17 : 1,487.52 = 685.14 : x
2. Step 2: Convert to fraction form
   1,078.17/1,487.52 = 685.14/x
3. Step 3: Cross multiply
   1,078.17x = 1,487.52 × 685.14
4. Step 4: Simplify right side
   1,078.17x = 1,019,159.45
5. Step 5: Solve for x
   x = 1,019,159.45/1,078.17
6. Step 6: Final answer
   x = 945.27