Finding the Fourth Proportional to 20,709.81, 28,581.53 and 12,756.69

Step by Step Solution

1. Step 1: Write the proportion equation
   20,709.81 : 28,581.53 = 12,756.69 : x
2. Step 2: Convert to fraction form
   20,709.81/28,581.53 = 12,756.69/x
3. Step 3: Cross multiply
   20,709.81x = 28,581.53 × 12,756.69
4. Step 4: Simplify right side
   20,709.81x = 364,605,654.15
5. Step 5: Solve for x
   x = 364,605,654.15/20,709.81
6. Step 6: Final answer
   x = 17,605.46