Finding the Fourth Proportional to 8,298.45, 12,429.45 and 8,116.20

Step by Step Solution

1. Step 1: Write the proportion equation
   8,298.45 : 12,429.45 = 8,116.20 : x
2. Step 2: Convert to fraction form
   8,298.45/12,429.45 = 8,116.20/x
3. Step 3: Cross multiply
   8,298.45x = 12,429.45 × 8,116.20
4. Step 4: Simplify right side
   8,298.45x = 100,879,902.09
5. Step 5: Solve for x
   x = 100,879,902.09/8,298.45
6. Step 6: Final answer
   x = 12,156.48