Finding the Fourth Proportional to 1,405.10, 1,939.03 and 775.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.10 : 1,939.03 = 775.63 : x
2. Step 2: Convert to fraction form
   1,405.10/1,939.03 = 775.63/x
3. Step 3: Cross multiply
   1,405.10x = 1,939.03 × 775.63
4. Step 4: Simplify right side
   1,405.10x = 1,503,963.05
5. Step 5: Solve for x
   x = 1,503,963.05/1,405.10
6. Step 6: Final answer
   x = 1,070.36