Finding the Fourth Proportional to 11,308.72, 15,616.92 and 7,780.36

Step by Step Solution

1. Step 1: Write the proportion equation
   11,308.72 : 15,616.92 = 7,780.36 : x
2. Step 2: Convert to fraction form
   11,308.72/15,616.92 = 7,780.36/x
3. Step 3: Cross multiply
   11,308.72x = 15,616.92 × 7,780.36
4. Step 4: Simplify right side
   11,308.72x = 121,505,259.69
5. Step 5: Solve for x
   x = 121,505,259.69/11,308.72
6. Step 6: Final answer
   x = 10,744.39