Finding the Fourth Proportional to 5,425.57, 8,139.72 and 2,505.91

Step by Step Solution

1. Step 1: Write the proportion equation
   5,425.57 : 8,139.72 = 2,505.91 : x
2. Step 2: Convert to fraction form
   5,425.57/8,139.72 = 2,505.91/x
3. Step 3: Cross multiply
   5,425.57x = 8,139.72 × 2,505.91
4. Step 4: Simplify right side
   5,425.57x = 20,397,405.75
5. Step 5: Solve for x
   x = 20,397,405.75/5,425.57
6. Step 6: Final answer
   x = 3,759.50