Finding the Fourth Proportional to 8,111.64, 12,168.69 and 3,431.65

Step by Step Solution

1. Step 1: Write the proportion equation
   8,111.64 : 12,168.69 = 3,431.65 : x
2. Step 2: Convert to fraction form
   8,111.64/12,168.69 = 3,431.65/x
3. Step 3: Cross multiply
   8,111.64x = 12,168.69 × 3,431.65
4. Step 4: Simplify right side
   8,111.64x = 41,758,685.04
5. Step 5: Solve for x
   x = 41,758,685.04/8,111.64
6. Step 6: Final answer
   x = 5,148.00