Finding the Fourth Proportional to 15,505.47, 21,395.90 and 9,131.69

Step by Step Solution

1. Step 1: Write the proportion equation
   15,505.47 : 21,395.90 = 9,131.69 : x
2. Step 2: Convert to fraction form
   15,505.47/21,395.90 = 9,131.69/x
3. Step 3: Cross multiply
   15,505.47x = 21,395.90 × 9,131.69
4. Step 4: Simplify right side
   15,505.47x = 195,380,573.43
5. Step 5: Solve for x
   x = 195,380,573.43/15,505.47
6. Step 6: Final answer
   x = 12,600.75