Finding the Fourth Proportional to 6,327.20, 8,729.42 and 4,091.90

Step by Step Solution

1. Step 1: Write the proportion equation
   6,327.20 : 8,729.42 = 4,091.90 : x
2. Step 2: Convert to fraction form
   6,327.20/8,729.42 = 4,091.90/x
3. Step 3: Cross multiply
   6,327.20x = 8,729.42 × 4,091.90
4. Step 4: Simplify right side
   6,327.20x = 35,719,849.59
5. Step 5: Solve for x
   x = 35,719,849.59/6,327.20
6. Step 6: Final answer
   x = 5,645.45