Finding the Fourth Proportional to 12,646.63, 17,429.22 and 8,390.18

Step by Step Solution

1. Step 1: Write the proportion equation
   12,646.63 : 17,429.22 = 8,390.18 : x
2. Step 2: Convert to fraction form
   12,646.63/17,429.22 = 8,390.18/x
3. Step 3: Cross multiply
   12,646.63x = 17,429.22 × 8,390.18
4. Step 4: Simplify right side
   12,646.63x = 146,234,293.06
5. Step 5: Solve for x
   x = 146,234,293.06/12,646.63
6. Step 6: Final answer
   x = 11,563.10