Finding the Fourth Proportional to 8,578.72, 12,869.94 and 3,384.64

Step by Step Solution

1. Step 1: Write the proportion equation
   8,578.72 : 12,869.94 = 3,384.64 : x
2. Step 2: Convert to fraction form
   8,578.72/12,869.94 = 3,384.64/x
3. Step 3: Cross multiply
   8,578.72x = 12,869.94 × 3,384.64
4. Step 4: Simplify right side
   8,578.72x = 43,560,113.72
5. Step 5: Solve for x
   x = 43,560,113.72/8,578.72
6. Step 6: Final answer
   x = 5,077.69