Finding the Fourth Proportional to 14,520.20, 21,783.94 and 7,128.14

Step by Step Solution

1. Step 1: Write the proportion equation
   14,520.20 : 21,783.94 = 7,128.14 : x
2. Step 2: Convert to fraction form
   14,520.20/21,783.94 = 7,128.14/x
3. Step 3: Cross multiply
   14,520.20x = 21,783.94 × 7,128.14
4. Step 4: Simplify right side
   14,520.20x = 155,278,847.33
5. Step 5: Solve for x
   x = 155,278,847.33/14,520.20
6. Step 6: Final answer
   x = 10,693.99