Finding the Fourth Proportional to 9,414.28, 12,991.92 and 5,222.80

Step by Step Solution

1. Step 1: Write the proportion equation
   9,414.28 : 12,991.92 = 5,222.80 : x
2. Step 2: Convert to fraction form
   9,414.28/12,991.92 = 5,222.80/x
3. Step 3: Cross multiply
   9,414.28x = 12,991.92 × 5,222.80
4. Step 4: Simplify right side
   9,414.28x = 67,854,199.78
5. Step 5: Solve for x
   x = 67,854,199.78/9,414.28
6. Step 6: Final answer
   x = 7,207.58