Finding the Fourth Proportional to 3,947.40, 5,929.29 and 3,131.37

Step by Step Solution

1. Step 1: Write the proportion equation
   3,947.40 : 5,929.29 = 3,131.37 : x
2. Step 2: Convert to fraction form
   3,947.40/5,929.29 = 3,131.37/x
3. Step 3: Cross multiply
   3,947.40x = 5,929.29 × 3,131.37
4. Step 4: Simplify right side
   3,947.40x = 18,566,800.83
5. Step 5: Solve for x
   x = 18,566,800.83/3,947.40
6. Step 6: Final answer
   x = 4,703.55