Finding the Fourth Proportional to 3,992.31, 5,509.61 and 2,399.45

Step by Step Solution

1. Step 1: Write the proportion equation
   3,992.31 : 5,509.61 = 2,399.45 : x
2. Step 2: Convert to fraction form
   3,992.31/5,509.61 = 2,399.45/x
3. Step 3: Cross multiply
   3,992.31x = 5,509.61 × 2,399.45
4. Step 4: Simplify right side
   3,992.31x = 13,220,033.71
5. Step 5: Solve for x
   x = 13,220,033.71/3,992.31
6. Step 6: Final answer
   x = 3,311.37