Finding the Fourth Proportional to 16,256.94, 22,420.71 and 12,489.18

Step by Step Solution

1. Step 1: Write the proportion equation
   16,256.94 : 22,420.71 = 12,489.18 : x
2. Step 2: Convert to fraction form
   16,256.94/22,420.71 = 12,489.18/x
3. Step 3: Cross multiply
   16,256.94x = 22,420.71 × 12,489.18
4. Step 4: Simplify right side
   16,256.94x = 280,016,282.92
5. Step 5: Solve for x
   x = 280,016,282.92/16,256.94
6. Step 6: Final answer
   x = 17,224.42