Finding the Fourth Proportional to 20,667.99, 28,495.41 and 13,387.23

Step by Step Solution

1. Step 1: Write the proportion equation
   20,667.99 : 28,495.41 = 13,387.23 : x
2. Step 2: Convert to fraction form
   20,667.99/28,495.41 = 13,387.23/x
3. Step 3: Cross multiply
   20,667.99x = 28,495.41 × 13,387.23
4. Step 4: Simplify right side
   20,667.99x = 381,474,607.61
5. Step 5: Solve for x
   x = 381,474,607.61/20,667.99
6. Step 6: Final answer
   x = 18,457.27