Finding the Fourth Proportional to 12,724.05, 17,559.36 and 7,687.56

Step by Step Solution

1. Step 1: Write the proportion equation
   12,724.05 : 17,559.36 = 7,687.56 : x
2. Step 2: Convert to fraction form
   12,724.05/17,559.36 = 7,687.56/x
3. Step 3: Cross multiply
   12,724.05x = 17,559.36 × 7,687.56
4. Step 4: Simplify right side
   12,724.05x = 134,988,633.56
5. Step 5: Solve for x
   x = 134,988,633.56/12,724.05
6. Step 6: Final answer
   x = 10,608.94