Finding the Fourth Proportional to 8,978.36, 12,386.77 and 5,200.14

Step by Step Solution

1. Step 1: Write the proportion equation
   8,978.36 : 12,386.77 = 5,200.14 : x
2. Step 2: Convert to fraction form
   8,978.36/12,386.77 = 5,200.14/x
3. Step 3: Cross multiply
   8,978.36x = 12,386.77 × 5,200.14
4. Step 4: Simplify right side
   8,978.36x = 64,412,943.11
5. Step 5: Solve for x
   x = 64,412,943.11/8,978.36
6. Step 6: Final answer
   x = 7,174.25