Finding the Fourth Proportional to 2,073.69, 3,109.61 and 840.76

Step by Step Solution

1. Step 1: Write the proportion equation
   2,073.69 : 3,109.61 = 840.76 : x
2. Step 2: Convert to fraction form
   2,073.69/3,109.61 = 840.76/x
3. Step 3: Cross multiply
   2,073.69x = 3,109.61 × 840.76
4. Step 4: Simplify right side
   2,073.69x = 2,614,435.70
5. Step 5: Solve for x
   x = 2,614,435.70/2,073.69
6. Step 6: Final answer
   x = 1,260.76