Finding the Fourth Proportional to 12,724.43, 17,559.90 and 7,687.96

Step by Step Solution

1. Step 1: Write the proportion equation
   12,724.43 : 17,559.90 = 7,687.96 : x
2. Step 2: Convert to fraction form
   12,724.43/17,559.90 = 7,687.96/x
3. Step 3: Cross multiply
   12,724.43x = 17,559.90 × 7,687.96
4. Step 4: Simplify right side
   12,724.43x = 134,999,764.90
5. Step 5: Solve for x
   x = 134,999,764.90/12,724.43
6. Step 6: Final answer
   x = 10,609.50