Finding the Fourth Proportional to 8,111.20, 12,160.05 and 3,434.80

Step by Step Solution

1. Step 1: Write the proportion equation
   8,111.20 : 12,160.05 = 3,434.80 : x
2. Step 2: Convert to fraction form
   8,111.20/12,160.05 = 3,434.80/x
3. Step 3: Cross multiply
   8,111.20x = 12,160.05 × 3,434.80
4. Step 4: Simplify right side
   8,111.20x = 41,767,339.74
5. Step 5: Solve for x
   x = 41,767,339.74/8,111.20
6. Step 6: Final answer
   x = 5,149.34