Finding the Fourth Proportional to 9,399.72, 12,972.12 and 5,208

Step by Step Solution

1. Step 1: Write the proportion equation
   9,399.72 : 12,972.12 = 5,208 : x
2. Step 2: Convert to fraction form
   9,399.72/12,972.12 = 5,208/x
3. Step 3: Cross multiply
   9,399.72x = 12,972.12 × 5,208
4. Step 4: Simplify right side
   9,399.72x = 67,558,800.96
5. Step 5: Solve for x
   x = 67,558,800.96/9,399.72
6. Step 6: Final answer
   x = 7,187.32