Finding the Fourth Proportional to 20,636.10, 28,478.25 and 12,144.42

Step by Step Solution

1. Step 1: Write the proportion equation
   20,636.10 : 28,478.25 = 12,144.42 : x
2. Step 2: Convert to fraction form
   20,636.10/28,478.25 = 12,144.42/x
3. Step 3: Cross multiply
   20,636.10x = 28,478.25 × 12,144.42
4. Step 4: Simplify right side
   20,636.10x = 345,851,828.87
5. Step 5: Solve for x
   x = 345,851,828.87/20,636.10
6. Step 6: Final answer
   x = 16,759.55