Finding the Fourth Proportional to 21,789.60, 30,068.56 and 12,228.32

Step by Step Solution

1. Step 1: Write the proportion equation
   21,789.60 : 30,068.56 = 12,228.32 : x
2. Step 2: Convert to fraction form
   21,789.60/30,068.56 = 12,228.32/x
3. Step 3: Cross multiply
   21,789.60x = 30,068.56 × 12,228.32
4. Step 4: Simplify right side
   21,789.60x = 367,687,973.62
5. Step 5: Solve for x
   x = 367,687,973.62/21,789.60
6. Step 6: Final answer
   x = 16,874.47