Finding the Fourth Proportional to 3,831.31, 5,287.21 and 2,152.72

Step by Step Solution

1. Step 1: Write the proportion equation
   3,831.31 : 5,287.21 = 2,152.72 : x
2. Step 2: Convert to fraction form
   3,831.31/5,287.21 = 2,152.72/x
3. Step 3: Cross multiply
   3,831.31x = 5,287.21 × 2,152.72
4. Step 4: Simplify right side
   3,831.31x = 11,381,874.87
5. Step 5: Solve for x
   x = 11,381,874.87/3,831.31
6. Step 6: Final answer
   x = 2,970.75