Finding the Fourth Proportional to 1,355.89, 1,871.10 and 758.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.89 : 1,871.10 = 758.40 : x
2. Step 2: Convert to fraction form
   1,355.89/1,871.10 = 758.40/x
3. Step 3: Cross multiply
   1,355.89x = 1,871.10 × 758.40
4. Step 4: Simplify right side
   1,355.89x = 1,419,042.24
5. Step 5: Solve for x
   x = 1,419,042.24/1,355.89
6. Step 6: Final answer
   x = 1,046.58