Finding the Fourth Proportional to 1,404.85, 1,938.70 and 775.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,404.85 : 1,938.70 = 775.40 : x
2. Step 2: Convert to fraction form
   1,404.85/1,938.70 = 775.40/x
3. Step 3: Cross multiply
   1,404.85x = 1,938.70 × 775.40
4. Step 4: Simplify right side
   1,404.85x = 1,503,267.98
5. Step 5: Solve for x
   x = 1,503,267.98/1,404.85
6. Step 6: Final answer
   x = 1,070.06