Finding the Fourth Proportional to 22,456, 30,989.28 and 12,520

Step by Step Solution

1. Step 1: Write the proportion equation
   22,456 : 30,989.28 = 12,520 : x
2. Step 2: Convert to fraction form
   22,456/30,989.28 = 12,520/x
3. Step 3: Cross multiply
   22,456x = 30,989.28 × 12,520
4. Step 4: Simplify right side
   22,456x = 387,985,785.60
5. Step 5: Solve for x
   x = 387,985,785.60/22,456
6. Step 6: Final answer
   x = 17,277.60