Finding the Fourth Proportional to 3,107.69, 4,287.56 and 2,111.23

Step by Step Solution

1. Step 1: Write the proportion equation
   3,107.69 : 4,287.56 = 2,111.23 : x
2. Step 2: Convert to fraction form
   3,107.69/4,287.56 = 2,111.23/x
3. Step 3: Cross multiply
   3,107.69x = 4,287.56 × 2,111.23
4. Step 4: Simplify right side
   3,107.69x = 9,052,025.30
5. Step 5: Solve for x
   x = 9,052,025.30/3,107.69
6. Step 6: Final answer
   x = 2,912.78