Finding the Fourth Proportional to 9,288.72, 13,920.42 and 5,122.47

Step by Step Solution

1. Step 1: Write the proportion equation
   9,288.72 : 13,920.42 = 5,122.47 : x
2. Step 2: Convert to fraction form
   9,288.72/13,920.42 = 5,122.47/x
3. Step 3: Cross multiply
   9,288.72x = 13,920.42 × 5,122.47
4. Step 4: Simplify right side
   9,288.72x = 71,306,933.84
5. Step 5: Solve for x
   x = 71,306,933.84/9,288.72
6. Step 6: Final answer
   x = 7,676.72