Finding the Fourth Proportional to 12,687.31, 17,508.53 and 7,022.45

Step by Step Solution

1. Step 1: Write the proportion equation
   12,687.31 : 17,508.53 = 7,022.45 : x
2. Step 2: Convert to fraction form
   12,687.31/17,508.53 = 7,022.45/x
3. Step 3: Cross multiply
   12,687.31x = 17,508.53 × 7,022.45
4. Step 4: Simplify right side
   12,687.31x = 122,952,844.32
5. Step 5: Solve for x
   x = 122,952,844.32/12,687.31
6. Step 6: Final answer
   x = 9,691.01