Finding the Fourth Proportional to 2,227.69, 3,340.62 and 840.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,227.69 : 3,340.62 = 840.31 : x
2. Step 2: Convert to fraction form
   2,227.69/3,340.62 = 840.31/x
3. Step 3: Cross multiply
   2,227.69x = 3,340.62 × 840.31
4. Step 4: Simplify right side
   2,227.69x = 2,807,156.39
5. Step 5: Solve for x
   x = 2,807,156.39/2,227.69
6. Step 6: Final answer
   x = 1,260.12