Finding the Fourth Proportional to 3,711.52, 5,123.75 and 2,139.31

Step by Step Solution

1. Step 1: Write the proportion equation
   3,711.52 : 5,123.75 = 2,139.31 : x
2. Step 2: Convert to fraction form
   3,711.52/5,123.75 = 2,139.31/x
3. Step 3: Cross multiply
   3,711.52x = 5,123.75 × 2,139.31
4. Step 4: Simplify right side
   3,711.52x = 10,961,289.61
5. Step 5: Solve for x
   x = 10,961,289.61/3,711.52
6. Step 6: Final answer
   x = 2,953.32