Finding the Fourth Proportional to 12,620.30, 17,406.75 and 8,141.78

Step by Step Solution

1. Step 1: Write the proportion equation
   12,620.30 : 17,406.75 = 8,141.78 : x
2. Step 2: Convert to fraction form
   12,620.30/17,406.75 = 8,141.78/x
3. Step 3: Cross multiply
   12,620.30x = 17,406.75 × 8,141.78
4. Step 4: Simplify right side
   12,620.30x = 141,721,929.02
5. Step 5: Solve for x
   x = 141,721,929.02/12,620.30
6. Step 6: Final answer
   x = 11,229.68