Finding the Fourth Proportional to 8,921.16, 12,309.40 and 5,384.56

Step by Step Solution

1. Step 1: Write the proportion equation
   8,921.16 : 12,309.40 = 5,384.56 : x
2. Step 2: Convert to fraction form
   8,921.16/12,309.40 = 5,384.56/x
3. Step 3: Cross multiply
   8,921.16x = 12,309.40 × 5,384.56
4. Step 4: Simplify right side
   8,921.16x = 66,280,702.86
5. Step 5: Solve for x
   x = 66,280,702.86/8,921.16
6. Step 6: Final answer
   x = 7,429.61