Finding the Fourth Proportional to 1,831.50, 2,745.72 and 857.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,831.50 : 2,745.72 = 857.40 : x
2. Step 2: Convert to fraction form
   1,831.50/2,745.72 = 857.40/x
3. Step 3: Cross multiply
   1,831.50x = 2,745.72 × 857.40
4. Step 4: Simplify right side
   1,831.50x = 2,354,180.33
5. Step 5: Solve for x
   x = 2,354,180.33/1,831.50
6. Step 6: Final answer
   x = 1,285.38