Finding the Fourth Proportional to 8,085.42, 12,105.64 and 4,128.13

Step by Step Solution

1. Step 1: Write the proportion equation
   8,085.42 : 12,105.64 = 4,128.13 : x
2. Step 2: Convert to fraction form
   8,085.42/12,105.64 = 4,128.13/x
3. Step 3: Cross multiply
   8,085.42x = 12,105.64 × 4,128.13
4. Step 4: Simplify right side
   8,085.42x = 49,973,652.72
5. Step 5: Solve for x
   x = 49,973,652.72/8,085.42
6. Step 6: Final answer
   x = 6,180.71