Finding the Fourth Proportional to 12,128.20, 16,714.98 and 9,123.64

Step by Step Solution

1. Step 1: Write the proportion equation
   12,128.20 : 16,714.98 = 9,123.64 : x
2. Step 2: Convert to fraction form
   12,128.20/16,714.98 = 9,123.64/x
3. Step 3: Cross multiply
   12,128.20x = 16,714.98 × 9,123.64
4. Step 4: Simplify right side
   12,128.20x = 152,501,460.13
5. Step 5: Solve for x
   x = 152,501,460.13/12,128.20
6. Step 6: Final answer
   x = 12,574.12