Finding the Fourth Proportional to 10,506.78, 15,789.12 and 5,580.12

Step by Step Solution

1. Step 1: Write the proportion equation
   10,506.78 : 15,789.12 = 5,580.12 : x
2. Step 2: Convert to fraction form
   10,506.78/15,789.12 = 5,580.12/x
3. Step 3: Cross multiply
   10,506.78x = 15,789.12 × 5,580.12
4. Step 4: Simplify right side
   10,506.78x = 88,105,184.29
5. Step 5: Solve for x
   x = 88,105,184.29/10,506.78
6. Step 6: Final answer
   x = 8,385.56