Finding the Fourth Proportional to 5,425.90, 8,141.55 and 2,139.10

Step by Step Solution

1. Step 1: Write the proportion equation
   5,425.90 : 8,141.55 = 2,139.10 : x
2. Step 2: Convert to fraction form
   5,425.90/8,141.55 = 2,139.10/x
3. Step 3: Cross multiply
   5,425.90x = 8,141.55 × 2,139.10
4. Step 4: Simplify right side
   5,425.90x = 17,415,589.61
5. Step 5: Solve for x
   x = 17,415,589.61/5,425.90
6. Step 6: Final answer
   x = 3,209.71