Finding the Fourth Proportional to 1,147.20, 1,580.32 and 831.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,147.20 : 1,580.32 = 831.52 : x
2. Step 2: Convert to fraction form
   1,147.20/1,580.32 = 831.52/x
3. Step 3: Cross multiply
   1,147.20x = 1,580.32 × 831.52
4. Step 4: Simplify right side
   1,147.20x = 1,314,067.69
5. Step 5: Solve for x
   x = 1,314,067.69/1,147.20
6. Step 6: Final answer
   x = 1,145.46