Finding the Fourth Proportional to 11,806.50, 17,710.56 and 3,909

Step by Step Solution

1. Step 1: Write the proportion equation
   11,806.50 : 17,710.56 = 3,909 : x
2. Step 2: Convert to fraction form
   11,806.50/17,710.56 = 3,909/x
3. Step 3: Cross multiply
   11,806.50x = 17,710.56 × 3,909
4. Step 4: Simplify right side
   11,806.50x = 69,230,579.04
5. Step 5: Solve for x
   x = 69,230,579.04/11,806.50
6. Step 6: Final answer
   x = 5,863.77