Finding the Fourth Proportional to 3,990.03, 5,505.60 and 2,311.59

Step by Step Solution

1. Step 1: Write the proportion equation
   3,990.03 : 5,505.60 = 2,311.59 : x
2. Step 2: Convert to fraction form
   3,990.03/5,505.60 = 2,311.59/x
3. Step 3: Cross multiply
   3,990.03x = 5,505.60 × 2,311.59
4. Step 4: Simplify right side
   3,990.03x = 12,726,689.90
5. Step 5: Solve for x
   x = 12,726,689.90/3,990.03
6. Step 6: Final answer
   x = 3,189.62