Finding the Fourth Proportional to 13,086.72, 19,601.28 and 8,455.68

Step by Step Solution

1. Step 1: Write the proportion equation
   13,086.72 : 19,601.28 = 8,455.68 : x
2. Step 2: Convert to fraction form
   13,086.72/19,601.28 = 8,455.68/x
3. Step 3: Cross multiply
   13,086.72x = 19,601.28 × 8,455.68
4. Step 4: Simplify right side
   13,086.72x = 165,742,151.27
5. Step 5: Solve for x
   x = 165,742,151.27/13,086.72
6. Step 6: Final answer
   x = 12,664.91