Finding the Fourth Proportional to 9,405.74, 12,979.38 and 5,155.98

Step by Step Solution

1. Step 1: Write the proportion equation
   9,405.74 : 12,979.38 = 5,155.98 : x
2. Step 2: Convert to fraction form
   9,405.74/12,979.38 = 5,155.98/x
3. Step 3: Cross multiply
   9,405.74x = 12,979.38 × 5,155.98
4. Step 4: Simplify right side
   9,405.74x = 66,921,423.69
5. Step 5: Solve for x
   x = 66,921,423.69/9,405.74
6. Step 6: Final answer
   x = 7,114.96