Finding the Fourth Proportional to 1,354.95, 1,869.89 and 831.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,354.95 : 1,869.89 = 831.15 : x
2. Step 2: Convert to fraction form
   1,354.95/1,869.89 = 831.15/x
3. Step 3: Cross multiply
   1,354.95x = 1,869.89 × 831.15
4. Step 4: Simplify right side
   1,354.95x = 1,554,154.92
5. Step 5: Solve for x
   x = 1,554,154.92/1,354.95
6. Step 6: Final answer
   x = 1,147.02