Finding the Fourth Proportional to 10,520.56, 15,753.92 and 10,209.12

Step by Step Solution

1. Step 1: Write the proportion equation
   10,520.56 : 15,753.92 = 10,209.12 : x
2. Step 2: Convert to fraction form
   10,520.56/15,753.92 = 10,209.12/x
3. Step 3: Cross multiply
   10,520.56x = 15,753.92 × 10,209.12
4. Step 4: Simplify right side
   10,520.56x = 160,833,659.75
5. Step 5: Solve for x
   x = 160,833,659.75/10,520.56
6. Step 6: Final answer
   x = 15,287.56