Finding the Fourth Proportional to 8,128.20, 12,190.38 and 3,508.68

Step by Step Solution

1. Step 1: Write the proportion equation
   8,128.20 : 12,190.38 = 3,508.68 : x
2. Step 2: Convert to fraction form
   8,128.20/12,190.38 = 3,508.68/x
3. Step 3: Cross multiply
   8,128.20x = 12,190.38 × 3,508.68
4. Step 4: Simplify right side
   8,128.20x = 42,772,142.50
5. Step 5: Solve for x
   x = 42,772,142.50/8,128.20
6. Step 6: Final answer
   x = 5,262.19