Finding the Fourth Proportional to 3,990.54, 5,506.73 and 2,311.81

Step by Step Solution

1. Step 1: Write the proportion equation
   3,990.54 : 5,506.73 = 2,311.81 : x
2. Step 2: Convert to fraction form
   3,990.54/5,506.73 = 2,311.81/x
3. Step 3: Cross multiply
   3,990.54x = 5,506.73 × 2,311.81
4. Step 4: Simplify right side
   3,990.54x = 12,730,501.92
5. Step 5: Solve for x
   x = 12,730,501.92/3,990.54
6. Step 6: Final answer
   x = 3,190.17