Finding the Fourth Proportional to 21,819.36, 30,109.57 and 12,259.62

Step by Step Solution

1. Step 1: Write the proportion equation
   21,819.36 : 30,109.57 = 12,259.62 : x
2. Step 2: Convert to fraction form
   21,819.36/30,109.57 = 12,259.62/x
3. Step 3: Cross multiply
   21,819.36x = 30,109.57 × 12,259.62
4. Step 4: Simplify right side
   21,819.36x = 369,131,825.27
5. Step 5: Solve for x
   x = 369,131,825.27/21,819.36
6. Step 6: Final answer
   x = 16,917.63