Finding the Fourth Proportional to 15,485.31, 21,369.76 and 8,411.72

Step by Step Solution

1. Step 1: Write the proportion equation
   15,485.31 : 21,369.76 = 8,411.72 : x
2. Step 2: Convert to fraction form
   15,485.31/21,369.76 = 8,411.72/x
3. Step 3: Cross multiply
   15,485.31x = 21,369.76 × 8,411.72
4. Step 4: Simplify right side
   15,485.31x = 179,756,309.71
5. Step 5: Solve for x
   x = 179,756,309.71/15,485.31
6. Step 6: Final answer
   x = 11,608.18