Finding the Fourth Proportional to 12,785.76, 17,644.17 and 7,120.35

Step by Step Solution

1. Step 1: Write the proportion equation
   12,785.76 : 17,644.17 = 7,120.35 : x
2. Step 2: Convert to fraction form
   12,785.76/17,644.17 = 7,120.35/x
3. Step 3: Cross multiply
   12,785.76x = 17,644.17 × 7,120.35
4. Step 4: Simplify right side
   12,785.76x = 125,632,665.86
5. Step 5: Solve for x
   x = 125,632,665.86/12,785.76
6. Step 6: Final answer
   x = 9,825.98