Finding the Fourth Proportional to 9,099.15, 12,555.81 and 5,120.18

Step by Step Solution

1. Step 1: Write the proportion equation
   9,099.15 : 12,555.81 = 5,120.18 : x
2. Step 2: Convert to fraction form
   9,099.15/12,555.81 = 5,120.18/x
3. Step 3: Cross multiply
   9,099.15x = 12,555.81 × 5,120.18
4. Step 4: Simplify right side
   9,099.15x = 64,288,007.25
5. Step 5: Solve for x
   x = 64,288,007.25/9,099.15
6. Step 6: Final answer
   x = 7,065.28