Finding the Fourth Proportional to 12,128.16, 18,165.92 and 7,434.22

Step by Step Solution

1. Step 1: Write the proportion equation
   12,128.16 : 18,165.92 = 7,434.22 : x
2. Step 2: Convert to fraction form
   12,128.16/18,165.92 = 7,434.22/x
3. Step 3: Cross multiply
   12,128.16x = 18,165.92 × 7,434.22
4. Step 4: Simplify right side
   12,128.16x = 135,049,445.78
5. Step 5: Solve for x
   x = 135,049,445.78/12,128.16
6. Step 6: Final answer
   x = 11,135.20