Finding the Fourth Proportional to 2,647.17, 3,969.61 and 1,086.09

Step by Step Solution

1. Step 1: Write the proportion equation
   2,647.17 : 3,969.61 = 1,086.09 : x
2. Step 2: Convert to fraction form
   2,647.17/3,969.61 = 1,086.09/x
3. Step 3: Cross multiply
   2,647.17x = 3,969.61 × 1,086.09
4. Step 4: Simplify right side
   2,647.17x = 4,311,353.72
5. Step 5: Solve for x
   x = 4,311,353.72/2,647.17
6. Step 6: Final answer
   x = 1,628.67