Finding the Fourth Proportional to 1,340.80, 1,850.46 and 781.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,340.80 : 1,850.46 = 781.42 : x
2. Step 2: Convert to fraction form
   1,340.80/1,850.46 = 781.42/x
3. Step 3: Cross multiply
   1,340.80x = 1,850.46 × 781.42
4. Step 4: Simplify right side
   1,340.80x = 1,445,986.45
5. Step 5: Solve for x
   x = 1,445,986.45/1,340.80
6. Step 6: Final answer
   x = 1,078.45