Finding the Fourth Proportional to 1,355.25, 1,870.13 and 831.29

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.25 : 1,870.13 = 831.29 : x
2. Step 2: Convert to fraction form
   1,355.25/1,870.13 = 831.29/x
3. Step 3: Cross multiply
   1,355.25x = 1,870.13 × 831.29
4. Step 4: Simplify right side
   1,355.25x = 1,554,606.86
5. Step 5: Solve for x
   x = 1,554,606.86/1,355.25
6. Step 6: Final answer
   x = 1,147.10