Finding the Fourth Proportional to 19,106.47, 28,665.40 and 9,118.72

Step by Step Solution

1. Step 1: Write the proportion equation
   19,106.47 : 28,665.40 = 9,118.72 : x
2. Step 2: Convert to fraction form
   19,106.47/28,665.40 = 9,118.72/x
3. Step 3: Cross multiply
   19,106.47x = 28,665.40 × 9,118.72
4. Step 4: Simplify right side
   19,106.47x = 261,391,612.96
5. Step 5: Solve for x
   x = 261,391,612.96/19,106.47
6. Step 6: Final answer
   x = 13,680.79