Finding the Fourth Proportional to 12,547.04, 18,934.42 and 12,128.78

Step by Step Solution

1. Step 1: Write the proportion equation
   12,547.04 : 18,934.42 = 12,128.78 : x
2. Step 2: Convert to fraction form
   12,547.04/18,934.42 = 12,128.78/x
3. Step 3: Cross multiply
   12,547.04x = 18,934.42 × 12,128.78
4. Step 4: Simplify right side
   12,547.04x = 229,651,414.61
5. Step 5: Solve for x
   x = 229,651,414.61/12,547.04
6. Step 6: Final answer
   x = 18,303.23