Finding the Fourth Proportional to 2,689.16, 4,033.56 and 840.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,689.16 : 4,033.56 = 840.10 : x
2. Step 2: Convert to fraction form
   2,689.16/4,033.56 = 840.10/x
3. Step 3: Cross multiply
   2,689.16x = 4,033.56 × 840.10
4. Step 4: Simplify right side
   2,689.16x = 3,388,593.76
5. Step 5: Solve for x
   x = 3,388,593.76/2,689.16
6. Step 6: Final answer
   x = 1,260.09