Finding the Fourth Proportional to 5,391.58, 8,081.89 and 4,090.31

Step by Step Solution

1. Step 1: Write the proportion equation
   5,391.58 : 8,081.89 = 4,090.31 : x
2. Step 2: Convert to fraction form
   5,391.58/8,081.89 = 4,090.31/x
3. Step 3: Cross multiply
   5,391.58x = 8,081.89 × 4,090.31
4. Step 4: Simplify right side
   5,391.58x = 33,057,445.46
5. Step 5: Solve for x
   x = 33,057,445.46/5,391.58
6. Step 6: Final answer
   x = 6,131.31