Finding the Fourth Proportional to 15,804.72, 21,810.84 and 8,731.60

Step by Step Solution

1. Step 1: Write the proportion equation
   15,804.72 : 21,810.84 = 8,731.60 : x
2. Step 2: Convert to fraction form
   15,804.72/21,810.84 = 8,731.60/x
3. Step 3: Cross multiply
   15,804.72x = 21,810.84 × 8,731.60
4. Step 4: Simplify right side
   15,804.72x = 190,443,530.54
5. Step 5: Solve for x
   x = 190,443,530.54/15,804.72
6. Step 6: Final answer
   x = 12,049.79