Finding the Fourth Proportional to 1,405.02, 1,939.04 and 775.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.02 : 1,939.04 = 775.60 : x
2. Step 2: Convert to fraction form
   1,405.02/1,939.04 = 775.60/x
3. Step 3: Cross multiply
   1,405.02x = 1,939.04 × 775.60
4. Step 4: Simplify right side
   1,405.02x = 1,503,919.42
5. Step 5: Solve for x
   x = 1,503,919.42/1,405.02
6. Step 6: Final answer
   x = 1,070.39