Finding the Fourth Proportional to 9,411.96, 12,990.06 and 5,221.56

Step by Step Solution

1. Step 1: Write the proportion equation
   9,411.96 : 12,990.06 = 5,221.56 : x
2. Step 2: Convert to fraction form
   9,411.96/12,990.06 = 5,221.56/x
3. Step 3: Cross multiply
   9,411.96x = 12,990.06 × 5,221.56
4. Step 4: Simplify right side
   9,411.96x = 67,828,377.69
5. Step 5: Solve for x
   x = 67,828,377.69/9,411.96
6. Step 6: Final answer
   x = 7,206.62