Finding the Fourth Proportional to 3,990.06, 5,505.71 and 2,311.34

Step by Step Solution

1. Step 1: Write the proportion equation
   3,990.06 : 5,505.71 = 2,311.34 : x
2. Step 2: Convert to fraction form
   3,990.06/5,505.71 = 2,311.34/x
3. Step 3: Cross multiply
   3,990.06x = 5,505.71 × 2,311.34
4. Step 4: Simplify right side
   3,990.06x = 12,725,528.67
5. Step 5: Solve for x
   x = 12,725,528.67/3,990.06
6. Step 6: Final answer
   x = 3,189.31