Finding the Fourth Proportional to 8,978.72, 12,389.09 and 5,202.36

Step by Step Solution

1. Step 1: Write the proportion equation
   8,978.72 : 12,389.09 = 5,202.36 : x
2. Step 2: Convert to fraction form
   8,978.72/12,389.09 = 5,202.36/x
3. Step 3: Cross multiply
   8,978.72x = 12,389.09 × 5,202.36
4. Step 4: Simplify right side
   8,978.72x = 64,452,480.24
5. Step 5: Solve for x
   x = 64,452,480.24/8,978.72
6. Step 6: Final answer
   x = 7,178.36