Finding the Fourth Proportional to 8,605.89, 12,876.21 and 5,097.78

Step by Step Solution

1. Step 1: Write the proportion equation
   8,605.89 : 12,876.21 = 5,097.78 : x
2. Step 2: Convert to fraction form
   8,605.89/12,876.21 = 5,097.78/x
3. Step 3: Cross multiply
   8,605.89x = 12,876.21 × 5,097.78
4. Step 4: Simplify right side
   8,605.89x = 65,640,085.81
5. Step 5: Solve for x
   x = 65,640,085.81/8,605.89
6. Step 6: Final answer
   x = 7,627.34