Finding the Fourth Proportional to 1,405.35, 1,939.37 and 775.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.35 : 1,939.37 = 775.89 : x
2. Step 2: Convert to fraction form
   1,405.35/1,939.37 = 775.89/x
3. Step 3: Cross multiply
   1,405.35x = 1,939.37 × 775.89
4. Step 4: Simplify right side
   1,405.35x = 1,504,737.79
5. Step 5: Solve for x
   x = 1,504,737.79/1,405.35
6. Step 6: Final answer
   x = 1,070.72