Finding the Fourth Proportional to 2,139.56, 3,208.52 and 1,028.80

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.56 : 3,208.52 = 1,028.80 : x
2. Step 2: Convert to fraction form
   2,139.56/3,208.52 = 1,028.80/x
3. Step 3: Cross multiply
   2,139.56x = 3,208.52 × 1,028.80
4. Step 4: Simplify right side
   2,139.56x = 3,300,925.38
5. Step 5: Solve for x
   x = 3,300,925.38/2,139.56
6. Step 6: Final answer
   x = 1,542.81