Finding the Fourth Proportional to 10,978.68, 16,468.04 and 5,139.39

Step by Step Solution

1. Step 1: Write the proportion equation
   10,978.68 : 16,468.04 = 5,139.39 : x
2. Step 2: Convert to fraction form
   10,978.68/16,468.04 = 5,139.39/x
3. Step 3: Cross multiply
   10,978.68x = 16,468.04 × 5,139.39
4. Step 4: Simplify right side
   10,978.68x = 84,635,654.40
5. Step 5: Solve for x
   x = 84,635,654.40/10,978.68
6. Step 6: Final answer
   x = 7,709.09