Finding the Fourth Proportional to 2,831.40, 3,906.18 and 2,043.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,831.40 : 3,906.18 = 2,043.72 : x
2. Step 2: Convert to fraction form
   2,831.40/3,906.18 = 2,043.72/x
3. Step 3: Cross multiply
   2,831.40x = 3,906.18 × 2,043.72
4. Step 4: Simplify right side
   2,831.40x = 7,983,138.19
5. Step 5: Solve for x
   x = 7,983,138.19/2,831.40
6. Step 6: Final answer
   x = 2,819.50