Finding the Fourth Proportional to 1,405.02, 1,938.90 and 775.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.02 : 1,938.90 = 775.55 : x
2. Step 2: Convert to fraction form
   1,405.02/1,938.90 = 775.55/x
3. Step 3: Cross multiply
   1,405.02x = 1,938.90 × 775.55
4. Step 4: Simplify right side
   1,405.02x = 1,503,713.90
5. Step 5: Solve for x
   x = 1,503,713.90/1,405.02
6. Step 6: Final answer
   x = 1,070.24