Finding the Fourth Proportional to 12,983.20, 19,449.20 and 12,061.60

Step by Step Solution

1. Step 1: Write the proportion equation
   12,983.20 : 19,449.20 = 12,061.60 : x
2. Step 2: Convert to fraction form
   12,983.20/19,449.20 = 12,061.60/x
3. Step 3: Cross multiply
   12,983.20x = 19,449.20 × 12,061.60
4. Step 4: Simplify right side
   12,983.20x = 234,588,470.72
5. Step 5: Solve for x
   x = 234,588,470.72/12,983.20
6. Step 6: Final answer
   x = 18,068.62