Finding the Fourth Proportional to 1,399.16, 1,930.80 and 769.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.16 : 1,930.80 = 769.69 : x
2. Step 2: Convert to fraction form
   1,399.16/1,930.80 = 769.69/x
3. Step 3: Cross multiply
   1,399.16x = 1,930.80 × 769.69
4. Step 4: Simplify right side
   1,399.16x = 1,486,117.45
5. Step 5: Solve for x
   x = 1,486,117.45/1,399.16
6. Step 6: Final answer
   x = 1,062.15