Finding the Fourth Proportional to 6,612.72, 9,128.42 and 3,959.62

Step by Step Solution

1. Step 1: Write the proportion equation
   6,612.72 : 9,128.42 = 3,959.62 : x
2. Step 2: Convert to fraction form
   6,612.72/9,128.42 = 3,959.62/x
3. Step 3: Cross multiply
   6,612.72x = 9,128.42 × 3,959.62
4. Step 4: Simplify right side
   6,612.72x = 36,145,074.40
5. Step 5: Solve for x
   x = 36,145,074.40/6,612.72
6. Step 6: Final answer
   x = 5,465.99