Finding the Fourth Proportional to 21,898.72, 30,215.76 and 12,464.80

Step by Step Solution

1. Step 1: Write the proportion equation
   21,898.72 : 30,215.76 = 12,464.80 : x
2. Step 2: Convert to fraction form
   21,898.72/30,215.76 = 12,464.80/x
3. Step 3: Cross multiply
   21,898.72x = 30,215.76 × 12,464.80
4. Step 4: Simplify right side
   21,898.72x = 376,633,405.25
5. Step 5: Solve for x
   x = 376,633,405.25/21,898.72
6. Step 6: Final answer
   x = 17,198.88