Finding the Fourth Proportional to 11,359.39, 15,662.55 and 7,776.09

Step by Step Solution

1. Step 1: Write the proportion equation
   11,359.39 : 15,662.55 = 7,776.09 : x
2. Step 2: Convert to fraction form
   11,359.39/15,662.55 = 7,776.09/x
3. Step 3: Cross multiply
   11,359.39x = 15,662.55 × 7,776.09
4. Step 4: Simplify right side
   11,359.39x = 121,793,398.43
5. Step 5: Solve for x
   x = 121,793,398.43/11,359.39
6. Step 6: Final answer
   x = 10,721.83