Finding the Fourth Proportional to 5,409.89, 7,454.57 and 3,991.33

Step by Step Solution

1. Step 1: Write the proportion equation
   5,409.89 : 7,454.57 = 3,991.33 : x
2. Step 2: Convert to fraction form
   5,409.89/7,454.57 = 3,991.33/x
3. Step 3: Cross multiply
   5,409.89x = 7,454.57 × 3,991.33
4. Step 4: Simplify right side
   5,409.89x = 29,753,648.88
5. Step 5: Solve for x
   x = 29,753,648.88/5,409.89
6. Step 6: Final answer
   x = 5,499.86