Finding the Fourth Proportional to 10,866.61, 16,290.06 and 3,939.49

Step by Step Solution

1. Step 1: Write the proportion equation
   10,866.61 : 16,290.06 = 3,939.49 : x
2. Step 2: Convert to fraction form
   10,866.61/16,290.06 = 3,939.49/x
3. Step 3: Cross multiply
   10,866.61x = 16,290.06 × 3,939.49
4. Step 4: Simplify right side
   10,866.61x = 64,174,528.47
5. Step 5: Solve for x
   x = 64,174,528.47/10,866.61
6. Step 6: Final answer
   x = 5,905.66