Finding the Fourth Proportional to 1,405.78, 1,940.04 and 784.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.78 : 1,940.04 = 784.78 : x
2. Step 2: Convert to fraction form
   1,405.78/1,940.04 = 784.78/x
3. Step 3: Cross multiply
   1,405.78x = 1,940.04 × 784.78
4. Step 4: Simplify right side
   1,405.78x = 1,522,504.59
5. Step 5: Solve for x
   x = 1,522,504.59/1,405.78
6. Step 6: Final answer
   x = 1,083.03