Finding the Fourth Proportional to 13,715.87, 20,610.72 and 13,309.92

Step by Step Solution

1. Step 1: Write the proportion equation
   13,715.87 : 20,610.72 = 13,309.92 : x
2. Step 2: Convert to fraction form
   13,715.87/20,610.72 = 13,309.92/x
3. Step 3: Cross multiply
   13,715.87x = 20,610.72 × 13,309.92
4. Step 4: Simplify right side
   13,715.87x = 274,327,034.34
5. Step 5: Solve for x
   x = 274,327,034.34/13,715.87
6. Step 6: Final answer
   x = 20,000.71