Finding the Fourth Proportional to 12,212.96, 16,857.12 and 8,436.80

Step by Step Solution

1. Step 1: Write the proportion equation
   12,212.96 : 16,857.12 = 8,436.80 : x
2. Step 2: Convert to fraction form
   12,212.96/16,857.12 = 8,436.80/x
3. Step 3: Cross multiply
   12,212.96x = 16,857.12 × 8,436.80
4. Step 4: Simplify right side
   12,212.96x = 142,220,150.02
5. Step 5: Solve for x
   x = 142,220,150.02/12,212.96
6. Step 6: Final answer
   x = 11,645.02