Finding the Fourth Proportional to 8,819.89, 12,172.41 and 5,636.12

Step by Step Solution

1. Step 1: Write the proportion equation
   8,819.89 : 12,172.41 = 5,636.12 : x
2. Step 2: Convert to fraction form
   8,819.89/12,172.41 = 5,636.12/x
3. Step 3: Cross multiply
   8,819.89x = 12,172.41 × 5,636.12
4. Step 4: Simplify right side
   8,819.89x = 68,605,102.59
5. Step 5: Solve for x
   x = 68,605,102.59/8,819.89
6. Step 6: Final answer
   x = 7,778.46