Finding the Fourth Proportional to 20,588.63, 28,404.19 and 13,426.89

Step by Step Solution

1. Step 1: Write the proportion equation
   20,588.63 : 28,404.19 = 13,426.89 : x
2. Step 2: Convert to fraction form
   20,588.63/28,404.19 = 13,426.89/x
3. Step 3: Cross multiply
   20,588.63x = 28,404.19 × 13,426.89
4. Step 4: Simplify right side
   20,588.63x = 381,379,962.59
5. Step 5: Solve for x
   x = 381,379,962.59/20,588.63
6. Step 6: Final answer
   x = 18,523.81