Finding the Fourth Proportional to 1,395.39, 1,925.67 and 789.68

Step by Step Solution

1. Step 1: Write the proportion equation
   1,395.39 : 1,925.67 = 789.68 : x
2. Step 2: Convert to fraction form
   1,395.39/1,925.67 = 789.68/x
3. Step 3: Cross multiply
   1,395.39x = 1,925.67 × 789.68
4. Step 4: Simplify right side
   1,395.39x = 1,520,667.90
5. Step 5: Solve for x
   x = 1,520,667.90/1,395.39
6. Step 6: Final answer
   x = 1,089.78