Finding the Fourth Proportional to 15,843.69, 21,866.58 and 9,128.03

Step by Step Solution

1. Step 1: Write the proportion equation
   15,843.69 : 21,866.58 = 9,128.03 : x
2. Step 2: Convert to fraction form
   15,843.69/21,866.58 = 9,128.03/x
3. Step 3: Cross multiply
   15,843.69x = 21,866.58 × 9,128.03
4. Step 4: Simplify right side
   15,843.69x = 199,598,688.90
5. Step 5: Solve for x
   x = 199,598,688.90/15,843.69
6. Step 6: Final answer
   x = 12,597.99