Finding the Fourth Proportional to 10,257.80, 14,155.78 and 5,542.09

Step by Step Solution

1. Step 1: Write the proportion equation
   10,257.80 : 14,155.78 = 5,542.09 : x
2. Step 2: Convert to fraction form
   10,257.80/14,155.78 = 5,542.09/x
3. Step 3: Cross multiply
   10,257.80x = 14,155.78 × 5,542.09
4. Step 4: Simplify right side
   10,257.80x = 78,452,557.54
5. Step 5: Solve for x
   x = 78,452,557.54/10,257.80
6. Step 6: Final answer
   x = 7,648.09