Finding the Fourth Proportional to 12,831.72, 17,707.60 and 7,166.58

Step by Step Solution

1. Step 1: Write the proportion equation
   12,831.72 : 17,707.60 = 7,166.58 : x
2. Step 2: Convert to fraction form
   12,831.72/17,707.60 = 7,166.58/x
3. Step 3: Cross multiply
   12,831.72x = 17,707.60 × 7,166.58
4. Step 4: Simplify right side
   12,831.72x = 126,902,932.01
5. Step 5: Solve for x
   x = 126,902,932.01/12,831.72
6. Step 6: Final answer
   x = 9,889.78