Finding the Fourth Proportional to 12,403.72, 17,112.90 and 7,686.28

Step by Step Solution

1. Step 1: Write the proportion equation
   12,403.72 : 17,112.90 = 7,686.28 : x
2. Step 2: Convert to fraction form
   12,403.72/17,112.90 = 7,686.28/x
3. Step 3: Cross multiply
   12,403.72x = 17,112.90 × 7,686.28
4. Step 4: Simplify right side
   12,403.72x = 131,534,541.01
5. Step 5: Solve for x
   x = 131,534,541.01/12,403.72
6. Step 6: Final answer
   x = 10,604.44