Finding the Fourth Proportional to 13,707.52, 20,580.72 and 13,081.12

Step by Step Solution

1. Step 1: Write the proportion equation
   13,707.52 : 20,580.72 = 13,081.12 : x
2. Step 2: Convert to fraction form
   13,707.52/20,580.72 = 13,081.12/x
3. Step 3: Cross multiply
   13,707.52x = 20,580.72 × 13,081.12
4. Step 4: Simplify right side
   13,707.52x = 269,218,868.01
5. Step 5: Solve for x
   x = 269,218,868.01/13,707.52
6. Step 6: Final answer
   x = 19,640.23