Finding the Fourth Proportional to 8,109.91, 12,147.76 and 5,146.79

Step by Step Solution

1. Step 1: Write the proportion equation
   8,109.91 : 12,147.76 = 5,146.79 : x
2. Step 2: Convert to fraction form
   8,109.91/12,147.76 = 5,146.79/x
3. Step 3: Cross multiply
   8,109.91x = 12,147.76 × 5,146.79
4. Step 4: Simplify right side
   8,109.91x = 62,521,938.04
5. Step 5: Solve for x
   x = 62,521,938.04/8,109.91
6. Step 6: Final answer
   x = 7,709.33