Finding the Fourth Proportional to 2,002.18, 3,002.12 and 831.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,002.18 : 3,002.12 = 831.20 : x
2. Step 2: Convert to fraction form
   2,002.18/3,002.12 = 831.20/x
3. Step 3: Cross multiply
   2,002.18x = 3,002.12 × 831.20
4. Step 4: Simplify right side
   2,002.18x = 2,495,362.14
5. Step 5: Solve for x
   x = 2,495,362.14/2,002.18
6. Step 6: Final answer
   x = 1,246.32