Finding the Fourth Proportional to 1,355.52, 1,870.56 and 831.36

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.52 : 1,870.56 = 831.36 : x
2. Step 2: Convert to fraction form
   1,355.52/1,870.56 = 831.36/x
3. Step 3: Cross multiply
   1,355.52x = 1,870.56 × 831.36
4. Step 4: Simplify right side
   1,355.52x = 1,555,108.76
5. Step 5: Solve for x
   x = 1,555,108.76/1,355.52
6. Step 6: Final answer
   x = 1,147.24