Finding the Fourth Proportional to 9,354.23, 12,908.78 and 5,105.21

Step by Step Solution

1. Step 1: Write the proportion equation
   9,354.23 : 12,908.78 = 5,105.21 : x
2. Step 2: Convert to fraction form
   9,354.23/12,908.78 = 5,105.21/x
3. Step 3: Cross multiply
   9,354.23x = 12,908.78 × 5,105.21
4. Step 4: Simplify right side
   9,354.23x = 65,901,990.54
5. Step 5: Solve for x
   x = 65,901,990.54/9,354.23
6. Step 6: Final answer
   x = 7,045.15