Finding the Fourth Proportional to 1,083.78, 1,495.87 and 685.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,083.78 : 1,495.87 = 685.42 : x
2. Step 2: Convert to fraction form
   1,083.78/1,495.87 = 685.42/x
3. Step 3: Cross multiply
   1,083.78x = 1,495.87 × 685.42
4. Step 4: Simplify right side
   1,083.78x = 1,025,293.76
5. Step 5: Solve for x
   x = 1,025,293.76/1,083.78
6. Step 6: Final answer
   x = 946.03