Finding the Fourth Proportional to 12,012.36, 18,018.81 and 3,128.04

Step by Step Solution

1. Step 1: Write the proportion equation
   12,012.36 : 18,018.81 = 3,128.04 : x
2. Step 2: Convert to fraction form
   12,012.36/18,018.81 = 3,128.04/x
3. Step 3: Cross multiply
   12,012.36x = 18,018.81 × 3,128.04
4. Step 4: Simplify right side
   12,012.36x = 56,363,558.43
5. Step 5: Solve for x
   x = 56,363,558.43/12,012.36
6. Step 6: Final answer
   x = 4,692.13